DIRECT SYNTHESIS METHOD OF NANOSTRUCTURED CATALYST PARTICLES ON VARIOUS SUPPORTS AND CATALYST STRUCTURE PRODUCED BY THE SAME
20170232431 · 2017-08-17
Inventors
- Namjo Jeong (Daejeon, KR)
- Chan-Soo Kim (Jeju, KR)
- Eun-Jin Jwa (Jeju, KR)
- Ji Yeon Choi (Seoul, KR)
- Joo-Youn Nam (Jeju, KR)
- Soon-Chul Park (Jeju, KR)
- Moon-Seok Jang (Daejeon, KR)
- Yong Seok SEO (Daejeon, KR)
- Kyo Sik Hwang (Jeju, KR)
- Han Ki Kim (Jeju, KR)
- Ji Hyung Han (Jeju, KR)
- Tae Young Kim (Jeonju, KR)
- Young Gi Yoon (Daejeon, KR)
Cpc classification
B01J23/8993
PERFORMING OPERATIONS; TRANSPORTING
B01J23/894
PERFORMING OPERATIONS; TRANSPORTING
B01J23/62
PERFORMING OPERATIONS; TRANSPORTING
B01J37/0238
PERFORMING OPERATIONS; TRANSPORTING
International classification
B01J37/02
PERFORMING OPERATIONS; TRANSPORTING
B01J21/06
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Disclosed is a direct synthesis method of nanostructured catalyst particles on surfaces of various supports. In the disclosed synthesis method of a catalyst structure having a plurality of nanostructured catalyst particles dispersed in a support by a one-step process using a high-temperature high-pressure closed reactor, the one-step process includes supplying the support and a catalyst source into the high-temperature high-pressure closed reactor; supplying an atmosphere forming gas of the reactor into the reactor; perfectly sealing the high-temperature high-pressure closed reactor and heating the reactor to produce the catalyst structure in the reactor under self-generated pressure and synthesis temperature conditions, the catalyst structure including the plurality of nanostructured catalyst particles dispersed in the support; removing internal gases of the reactor to allow the reactor to be in a high-temperature, atmospheric pressure state and supplying an inert gas into the reactor to remove unreacted materials and byproducts remaining in the reactor; and cooling the reactor to room temperature while supplying the inert gas to synthesize the catalyst structure.
Claims
1. A synthesis method of a catalyst structure having a plurality of nanostructured catalyst particles dispersed in a support by a one-step process using a high-temperature high-pressure closed reactor, wherein the one-step process comprises: supplying the support and a catalyst source into the high-temperature high-pressure closed reactor; perfectly sealing the high-temperature high-pressure closed reactor and heating the reactor to produce the catalyst structure in the reactor under self-generated pressure and synthesis temperature conditions, the catalyst structure including the plurality of nanostructured catalyst particles dispersed in the support; removing internal gases of the reactor to allow the reactor to be in a high-temperature, atmospheric pressure state and supplying an inert gas into the reactor to remove unreacted materials and byproducts remaining in the reactor; and cooling the reactor to room temperature while supplying the inert gas to synthesize the catalyst structure.
2. The synthesis method of claim 1, before the perfectly sealing of the high-temperature high-pressure closed reactor, further comprising supplying an atmosphere forming gas into the reactor.
3. The synthesis method of claim 1, before the cooling of the reactor to room temperature while supplying the inert gas, further comprising performing oxidation treatment, reduction treatment, doping treatment or a combination thereof.
4. The synthesis method of claim 3, wherein the oxidation treatment comprises supplying a mixed gas including an inert gas and oxygen, the reduction treatment comprises supplying a mixed gas including an inert gas and hydrogen, and the doping treatment comprises supplying a mixed gas including an inert gas and an ammonium gas.
5. The synthesis method of claim 1, before the supplying of the atmosphere forming gas into the reactor, further comprising elevating the temperature of the reactor to a temperature required to evaporate moisture while supplying the inert gas into the reactor, wherein the supplying of the inert gas is interrupted to then perfectly seal the high-temperature high-pressure closed reactor.
6. The synthesis method of claim 1, further comprising additionally performing the oxidation/reduction treatment, heat treatment or coating/doping treatment on the acquired catalyst structure using the closed reactor.
7. The synthesis method of claim 1, wherein at least some of the plurality of nanostructured catalyst particles are coated by a carbon shell or a doped carbon shell.
8. The synthesis method of claim 7, wherein the plurality of nanostructured catalyst particles form a stacked structure, in which neighboring ones of the nanostructured catalyst particles are separated from each other by the carbon shell or the doped carbon shell to prevent agglomeration of the nanostructured catalyst particles.
9. The synthesis method of claim 8, wherein the stacked structure is a single component stacked structure, a two or more component stacked structure, and a stacked structure formed by a combination of the single and two or more component stacked structures.
10. The synthesis method of claim 1, wherein the support is in the form of powder, a thin film, a foil, a foam, a mesh, a sheet, or a wire.
11. The synthesis method of claim 10, wherein the support includes a metal and the catalyst structure includes a Pt nanoparticle/Si nanoparticle support, a Pt alloy nanoparticle/Si nanoparticle support, a Co nanoparticle/Si nanoparticle support, a Co nanoparticle/Si nanoparticle support, a Co nanoflower/Si nanoparticle support, a Pt nanoparticle/Ti nanoparticle support, a Pt alloy nanoparticle/Ti nanoparticle support, a Pt alloy nanoparticle/Zn nanoparticle support, and a MoS.sub.2 nanostructure/Ti support.
12. The synthesis method of claim 10, wherein the support is a carbon support selected from the group consisting of carbon black, graphene, doped graphene, carbon nanotubes, carbon nanofibers, graphite and carbon spheres, and the catalyst structure is a MoS.sub.2 nanostructure/carbon support structure.
13. The synthesis method of claim 1, wherein the synthesized nanostructured catalyst particles include combined metal/non-metal nanostructured catalyst particles.
14. The synthesis method of claim 13, wherein the combined metal/non-metal nanostructured catalyst includes a MoS.sub.2—Pt nanostructure/the support, a MoS.sub.2—Pt alloy nanostructure/the support, a MoS.sub.2 shell-Pt core nanostructure/the support, or a MoS.sub.2 shell-Pt alloy core nanostructure/the support.
15. The synthesis method of claim 1, wherein the support is a hexagonal boron nitride support.
16. The synthesis method of claim 1, wherein the nanostructured catalyst particles are controlled to have a particle size of 2 nm or less.
17. The synthesis method of claim 1, wherein the catalyst source is used in dispersing the plurality of nanostructured catalyst particles in the support without loss.
18. The synthesis method of claim 1, wherein the synthesis temperature of the catalyst structure is higher than 200° C. and lower than 600° C.
19. The synthesis method of claim 1, wherein sizes or the dispersion density of the nanostructured catalyst particles are varied by controlling the content of a metal contained in the catalyst source or the synthesis temperature or by controlling the atmosphere forming gas.
20. A synthesis method of a catalyst structure having a plurality of nanostructured catalyst particles dispersed in a support by a one-step process using a high-temperature high-pressure closed reactor, wherein the one-step process comprises: supplying the support and a catalyst source into the high-temperature high-pressure closed reactor; perfectly sealing the high-temperature high-pressure closed reactor and heating the reactor to produce the catalyst structure in the reactor under a self-generated pressure of the reactor and a synthesis temperature in the range of 200° C. to 500° C., the catalyst structure including the plurality of nanostructured catalyst particles dispersed in the support;
21. A catalyst structure synthesized by the synthesis method of claim 1 and being in the form of a Pt nanoparticle/Si nanoparticle support, a Pt alloy nanoparticle/Si nanoparticle support, a Co nanoparticle/Si nanoparticle support, a Co nanoparticle/Si nanoparticle support, a Co nanoflower/Si nanoparticle support, a Pt nanoparticle/Ti nanoparticle support, a Pt alloy nanoparticle/Ti nanoparticle support, a Pt alloy nanoparticle/Zn nanoparticle support, and a MoS.sub.2 nanostructure/Ti support.
22. A catalyst structure synthesized by the synthesis method of claim 1, wherein the support is a carbon support selected from the group consisting of carbon black, graphene, doped graphene, carbon nanotubes, carbon nanofibers, graphite and carbon spheres, and the catalyst structure is a MoS.sub.2 nanostructure/the carbon support.
23. A catalyst structure synthesized by the synthesis method of claim 1, wherein the support is a hexagonal boron nitride support.
24. A catalyst structure synthesized by the synthesis method of claim 1, wherein combined metal/non-metal nanostructured catalyst particles are dispersed in the support.
25. The catalyst structure of claim 24, wherein the catalyst structure includes a MoS.sub.2—Pt nanostructure/the support, a MoS.sub.2—Pt alloy nanostructure/the support, a MoS.sub.2 shell-Pt core nanostructure/the support, or a MoS.sub.2 shell-Pt alloy core nanostructure/the support.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The above and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
[0025]
[0026]
[0027]
[0028]
[0029]
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
[0053]
[0054]
[0055]
[0056]
[0057]
[0058]
[0059]
[0060]
[0061]
[0062]
[0063]
[0064]
[0065]
[0066]
[0067]
[0068]
[0069]
[0070]
[0071]
[0072]
[0073]
[0074]
[0075]
[0076]
[0077]
[0078]
[0079]
[0080]
[0081]
[0082]
[0083]
[0084]
[0085]
[0086]
[0087]
[0088]
[0089]
[0090]
[0091]
[0092]
[0093]
[0094]
[0095]
[0096]
[0097]
[0098]
[0099]
[0100]
[0101]
[0102]
[0103]
[0104]
[0105]
[0106]
[0107]
[0108]
[0109]
[0110]
[0111]
[0112]
[0113]
[0114]
[0115]
[0116]
[0117]
[0118]
[0119]
[0120]
[0121]
[0122]
[0123]
[0124]
DETAILED DESCRIPTION
[0125] Hereinafter, examples of embodiments of the invention will be described in detail with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein.
[0126] A synthesis method of a catalyst structure having nanostructured catalyst particles dispersed in various types of supports according to embodiments of the present invention will now be described with reference to
[0127] First, a support and a catalyst source are supplied together into a high-temperature high-pressure closed reactor (S1).
[0128] The term “high-temperature high-pressure closed reactor” refers to a reactor that can be perfectly sealed under temperature pressure conditions required to cause reactions to take place. The term “high pressure” is used to mean a pressure higher than room temperature, that is, a pressure greater than or equal to 10 atm, a pressure greater than or equal to 20 atm, a pressure greater than or equal to 30 atm, or a pressure greater than or equal to 40 atm. The term “high temperature” refers to a temperature range exceeding at least 300° C. In embodiments of the present invention, the term “high temperature” may encompass a temperature ranging between 300° C. and 600° C.
[0129] The high-temperature high-pressure reactor can be modified in various types according to reaction materials, reaction conditions, and so on. The reactor volume may be at least 1 cc and may vary according to the design employed.
[0130] Any one of a carbon based support and a non-carbon based support can be used as the support. Usable examples of the carbon based support may include, but are not limited to, a zero-dimensional support, such as carbon spheres, a one-dimensional support, such as carbon nanotubes, a two-dimensional support, such as graphenes or N-doped graphenes, an amorphous support, such as other graphitized mesoporous carbon nanoparticles, carbon black, metal-carbon shell particles, or metal oxide-carbon shell particles, and a 3-dimensional support, such as combinations of the respective dimensional supports. Usable examples of the non-carbon based support may include metal oxide particles, such as Al.sub.2O.sub.3 particles, SiO.sub.2 particles, CeO.sub.2 particles, SnO.sub.2 particles, or ZnO particles, spinel type particles, such as CaAl.sub.2O.sub.4 particles or MgAl.sub.2O.sub.4 particles, other metal particles, such as Ti particles, Si particles, Zn particles, or the like, and besides non-metal support, such as boron nitride.
[0131] Nano-sized particles may be typically used as the support but micron-sized or larger particles may also be used as targets for catalyst coating. In addition, a non-powder support in the form of a bulk foil, a foam, a mesh, a wire or a sheet can also be used as the support.
[0132] Any one of a noble metal catalyst source, a non-noble metal catalyst source, and an organometallic catalyst source can be used as the catalyst source. Usable examples of the noble metal catalyst may include Pt, Ru, Ir, Rh, Pd, Au, Ag, Re and so on, and examples of the non-noble metal catalyst may include Fe, Co, Ni, Mn, Mo, Zn, V, Cr, Cu, Al, Ga, Ge, In, Sn, Sb and so on. Usable examples of the organometallic catalyst may include Fe based organic metal, Co based organic metal, Ni based organic metal, Mn based organic metal, Cu based organic metal, and Sn based organic metal.
[0133] Usable examples of the Pt source may include, but are not limited to, trimethyl(methylcyclopentadienyl) platinum (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3), platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4), and 1,5-Cyclooctadiene)dimethylplatinum (II) (C.sub.10H.sub.18Pt), usable examples of the Ru source may include, but are not limited to, ruthenium (III) acetylacetonate (Ru(C.sub.5H.sub.7O.sub.2).sub.3), ruthenocene (Ru(C.sub.5H.sub.5).sub.2), bis(ethylcyclopentadienyl) ruthenium (II) (C.sub.7H.sub.9RuC.sub.7H.sub.9), bis(2,4 dimethylpentadienyl)ruthenium (II) (C.sub.14H.sub.22Ru), and bis(pentamethylcyclopentadienyl)ruthenium (II) (Ru(C.sub.5(CH.sub.3).sub.5).sub.2, usable examples of the Ir sources may include, but are not limited to, methylcyclopentadienyl)(1,5-cycloctadiene)iridium (I), iridium (III) acetylacetonate (Ir(C.sub.5H.sub.7O.sub.2).sub.3), and (1,5-Cyclooctadiene)-η5-indenyeiridium (I) ((C.sub.9H.sub.7)Ir(C.sub.8H.sub.12)), usable examples of the Rh sources may include, but are not limited to, rhodium (III) acetylacetonate (Rh(C.sub.5H.sub.7O.sub.2).sub.3, and usable examples of the Pd source may include, but are not limited to, palladium (II) acetylacetonate (Pd(C.sub.5H.sub.7O.sub.2).sub.2. Usable examples of the Ag source may include, but are not limited to, silver cyanide (CAgN), and silver acetylacetonate (Ag(C.sub.5H.sub.7O.sub.2)), usable examples of the Au source may include, but are not limited to, gold cyanide (CAuN), and methyl(triphenylphosphine)gold (1) (C.sub.19H.sub.18AuP), and usable examples of the Re source may include, but are not limited to, rhenium carboxyl (C.sub.10O.sub.10Re.sub.2).
[0134] Usable examples of the Fe source may include, but are not limited to, ferrocene (C.sub.10H.sub.10Fe), vinyl ferrocene (C.sub.12H.sub.12Fe), and iron (III) acetylacetonate (Fe(C.sub.5H.sub.7O.sub.2).sub.3), usable examples of the Co source may include, but are not limited to, cobaltocene (C.sub.10H.sub.10Co), and cobalt (III) acetylacetonate (Co(C.sub.5H.sub.7O.sub.2).sub.3), usable examples of the Ni source may include, but are not limited to, nickelocene (C.sub.10H.sub.10Ni), and nickel (II) acetylacetonate (Ni(C.sub.5H.sub.7O.sub.2).sub.2), usable examples of the Mn source may include, but are not limited to, manganocene (C.sub.10H.sub.10Mn), manganese (II) acetylacetonate (Mn(C.sub.5H.sub.7O.sub.2).sub.2), vanadium(III) acetylacetonate (V(C.sub.5H.sub.7O.sub.2).sub.3), and chromium (III) acetylacetonate (Cr(C.sub.5H.sub.7O.sub.2).sub.3), usable examples of the Mo source may include, but are not limited to, bis(acetylacetonato)dioxomolybdenum (VI) (MoO.sub.2(C.sub.5H.sub.7O.sub.2).sub.2), bis(t-butylimido)bis(dimethylamino)molybdenum (VI) (C.sub.12H.sub.30MoN.sub.4), molybdenum (II) acetate dimer (CsH.sub.12Mo.sub.2O.sub.8), and molybdenum carboxyl (Mo(CO).sub.6), usable examples of the Zn source may include, but are not limited to, zinc(II) acetylacetonate (Zn(C.sub.5H.sub.7O.sub.2).sub.2 xH.sub.2O), diethylzinc (C.sub.4H.sub.10Zn), and dimethylzinc (C.sub.2H.sub.6Zn), usable examples of the Cu source may include, but are not limited to, copper(II) acetylacetonate (Cu(C.sub.5H.sub.7O.sub.2).sub.2), and copper cyanide (CCuN), Al sources may include, but are not limited to, aluminum (III) acetylacetonate (Al(C.sub.5H.sub.7O.sub.2).sub.3), trimethylaluminum (C.sub.3H.sub.9Al), trimethylaluminum (C.sub.6H.sub.15Al), and tri-butylaluminum (C.sub.12H.sub.27Al), usable examples of the Ga source may include, but are not limited to, gallium (III) acetylacetonate (Ga(C.sub.5H.sub.7O.sub.2).sub.3), usable examples of the In source may include, but are not limited to, indium (III) acetylacetonate (In(C.sub.5H.sub.7O.sub.2).sub.3), usable examples of the Sn source may include, but are not limited to, tin (II) acetylacetonate (Sn(C.sub.5H.sub.7O.sub.2).sub.2), tetramethyltin (C.sub.4H.sub.12Sn), and tetraphenyltin (C.sub.24H.sub.20Sn), usable examples of the Sb source may include, but are not limited to, antimony(III) acetate (C.sub.6H.sub.9O.sub.6Sb), triphenylantimony (C.sub.18H.sub.15Sb), and tris(dimethylamino)antimony ((CH.sub.3).sub.2N).sub.3Sb), and usable examples of the Ge source may include, but are not limited to, tetraethylgermanium (C.sub.8H.sub.20Ge), tetramethylgermanium (C.sub.4H.sub.12Ge), and tetra-butylgermanium (C.sub.16H.sub.36Ge).
[0135] Usable examples of the organometallic catalyst source may include, but are not limited to, iron (II) phthalocyanine (C.sub.32H.sub.16FeN.sub.8), iron porphyrin (C.sub.20H.sub.14FeN.sub.4), cobalt (II) phthalocyanine (C.sub.32H.sub.16CoN.sub.8), nickel (II) phthalocyanine (C.sub.32H.sub.16NiN.sub.8), manganese (II) phthalocyanine (C.sub.32H.sub.16MnN.sub.8), copper (II) phthalocyanine (C.sub.32H.sub.16CuN.sub.8), tin (II) phthalocyanine (C.sub.32H.sub.16SnN.sub.8).
[0136] When the noble metal catalyst source is used in combination with another catalyst source, a noble metal based binary alloy catalyst can be synthesized. When the Pt based catalyst source and the transition metal based catalyst source are used in combination, a Pt-transition metal based binary alloy catalyst can be synthesized. When the Pt based catalyst source and the organometallic catalyst source are used in combination, a Pt-organometal based binary alloy catalyst can be synthesized. When three or more catalyst sources are used in combination, a multicomponent alloy catalyst can be synthesized.
[0137] When the catalyst source is supplied into the reactor (S1), the content of catalyst contained in the substrate can be controlled to be in a desired range by controlling the content of the catalyst source supplied. The controlling of the content of the catalyst source supplied can be performed based on the weight ratio of the substrate and the catalyst source.
[0138] When the supplying of the catalyst source is completed, it is determined whether moisture contained in a sample needs to be removed from the reactor (S2).
[0139] When it is determined that moisture contained in a sample needs to be removed from the reactor, the temperature of the reactor is elevated to a temperature required to evaporate the moisture, e.g., up to 100° C., while supplying an inert gas into the reactor, and the elevated temperature is maintained for a predetermined time (S3). The step of removing the moisture (S4) is maintained for 1 to 60 minutes.
[0140] When it is not determined that moisture contained in a sample needs to be removed from the reactor, a reaction atmosphere gas required to create a reactor atmosphere to immediately cause a reaction is supplied (S4). For example, when a catalyst is prepared when a pure metal catalyst or a support is vulnerable to oxidation, an inert atmosphere without oxygen is required. In order to control the size of a catalyst based on, for example, platinum (Pt), an atmosphere with a trace amount of oxygen is required at an initial reaction stage. In addition, for nitrogen doping, it is necessary to supply a trace amount of ammonium gas before the reaction.
[0141] For the reasons stated above, an inert gas such as argon, nitrogen or helium, and a reactant such as oxygen or hydrogen, or an inert gas based mixed gas, including a slight amount of oxygen, hydrogen or ammonium, may be supplied as the reaction atmosphere gas.
[0142] The supplying of the reaction atmosphere gas may be controlled to be in the range of 1 to 10 atm relative to the volume of the reactor.
[0143] Next, the high-temperature high-pressure reactor is perfectly sealed and the temperature of the closed reactor is elevated (S5).
[0144] While the temperature of the reactor is elevated up to a reaction temperature, the internal pressure of the reactor is increased while the catalyst source is evaporated and dilated to then be subjected to thermal decomposition in the reactor. A self-generated pressure as much as a gas constant corresponding to a formation (or synthesis) temperature is produced in the reactor while the catalyst source is evaporated.
[0145] The reaction temperature may vary according to the material of the reactor or the reactor volume. In embodiments of the present invention, the reaction temperature is preferably in the range of 200° C. to 600° C. in consideration of economic efficiency of the reaction, particle size and dispersion density of nanostructured catalyst particles coated. When the reaction temperature is not higher than 200° C., nanostructured catalyst particles having a particle size of 1 nm or less may be synthesized. In this case, however, the catalyst source may not be properly decomposed and may not smoothly react with a surface of the support. When the reaction temperature is higher than 600° C., agglomeration of the nanostructured catalyst particles may be noticeably demonstrated. In addition, it is quite difficult to design the reactor and to select a material to be supplied to the reactor so as to cope with the distortion of the reactor, which may increase the manufacturing cost of the reactor, causing an increase in the production cost. The reaction temperature is more preferably in the range of 200° C. to 500° C. from standpoints of manufacturability and economic efficiency.
[0146] When the reactor reaches the reaction temperature (reaction pressure), the reaction is carried out for a predetermined time to synthesize the nanostructured catalyst particles on the support surface (S6).
[0147] The reaction time may be between 1 minute to 2 hours, which is, however, provided only for illustration and may vary according to the structural design of the catalyst to be synthesized (size, crystallinity, shape, etc.), the economic efficiency of reaction, the speed of chemical reaction between catalyst sources supplied.
[0148] After the reaction is completed, internal gases are removed from the reactor in the high-temperature high-pressure state to allow the reactor to be in a high-temperature, atmospheric-pressure state, and unreacted materials and byproducts remaining in the reactor are removed while supplying an inert gas (S7).
[0149] Then, it is checked whether additionally functioning of the reactor is required (S8).
[0150] If the additionally functioning is required, the reaction is carried out for a predetermined time while varying the temperature of the reactor up to a reaction temperature required for functioning the reactor and supplying reaction gases required (S9).
[0151] The functioning may include oxidation treatment, reduction treatment or a combination thereof.
[0152] The oxidation treatment may be performed by supplying an inert gas and oxygen-containing gas while maintaining the catalyst structure at a temperature higher than 200° C. and lower than 600° C. The oxidation treatment may be performed for approximately 1 to approximately 2 hours. When the acquired catalyst structure is maintained at a temperature of 200° C. or below, the oxidation reaction may not be sufficiently performed, and when the acquired catalyst structure is maintained at a temperature of 600° C. or higher, oxidation of the catalyst shell or the support may be facilitated and agglomeration of the nanostructured catalyst particles may be accelerated. When the nanostructured catalyst particles include a transition metal, a catalyst structure having transition-metal-oxide nanostructured catalyst particles dispersed in the support can be easily synthesized. When the nanostructured catalyst particles include a metal oxide, the activated oxygen adsorbed into the metal oxide or the interstitial oxygen of the metal oxide may be involved in an oxidation reaction and may function as a catalyst in the oxidation reaction. In addition, the metal oxide may also be used in dehydrogenation, condensation and decomposition of an oxygen-containing material as well as the oxidation reaction. Moreover, the metal oxide may be effectively used in removing ligands remaining on a catalyst surface.
[0153] Reduction treatment may be performed by supplying an inert gas and hydrogen-containing gas while maintaining the catalyst structure at a temperature higher than 200° C. and lower than 600° C. The reduction treatment may be performed for approximately 1 to approximately 2 hours. In particular, in a case of a metal catalyst, impurities can be removed from the surface of the catalyst structure through the reduction treatment. When the support includes an oxide, the reduction treatment may alter the oxide support into a support having a metallic property. When the acquired catalyst structure is maintained at a temperature of 200° C. or below, the reduction reaction may not be sufficiently performed. When the acquired catalyst structure is maintained at a temperature of 600° C. or higher, agglomeration of the nanostructured catalyst particles may be accelerated due to the high temperature.
[0154] When the additionally functioning is completed or the additionally functioning is not required, the reactor is cooled back to room temperature while supplying an inert gas and the catalyst structure having nanostructured catalyst particles dispersed in the support is then acquired in the reactor (S10).
[0155] The nanostructured catalyst particles in the acquired resultant product were uniformly distributed at all locations of the support, demonstrating a very high dispersion density. In addition, agglomeration of the nanostructured catalyst particles rarely occurs. Further, the nanostructured catalyst particles can be controlled to have a particle size of 2 nm or less, preferably approximately 1 nm.
[0156] The steps S1 to S10 are performed by a single process in which operations of the respective steps S1 to S10 take place within a single reactor. Therefore, according to embodiments of the present invention, since several to several tens of kilograms of the catalyst structure having nanostructured catalyst particles uniformly dispersed in the support is produced by the one-step process, high economic efficiency can be demonstrated.
[0157] In addition, the catalyst structure can be synthesized by dispersing the nanostructured catalyst particles in all locations of the support by the one-step process without artificially performing any functional treatment (addition of functional groups by surface oxidation, acid treatment, etc.) on the surface of the support.
[0158] According to embodiments of the present invention, it is possible to synthesize catalyst structures employing various kinds of materials, structures and components, including a metal, a non-metal, platinum, a non-platinum based catalyst material, and so on.
[0159] In addition, since the catalyst source (precursor) used for synthesizing a catalyst is fully dispersed on the support without loss, it is possible to accurately control the content of the catalyst to be contained in the catalyst structure, and incurred costs associated with the use of the catalyst source (precursor) can be remarkably reduced.
[0160] In addition, since the catalyst source evaporated under a high-temperature high-pressure closed atmosphere exists on all locations of the support surface in a constant concentration, it is possible to synthesize the nanostructured catalyst particles having a uniform size and an increased dispersion density on all locations of the support surface.
[0161] Moreover, it is possible to control the particle size of the synthesized nanostructured catalyst particles to be at least 1 nm, and the synthesized nanostructured catalyst particles can be produced to have a uniform particle size at all locations of the support in a uniform dispersion density.
[0162]
[0163] As illustrated in
[0164]
[0165] That is to say, compared to the conventional process in which at least two or three steps are performed, according to embodiments of the present invention, uniformly sized nanostructured catalyst particles can be dispersed on the support by a one-step process in an increased dispersion density, the processing cost can be reduced. In addition, since there is little material cost incurred in performing the process, high economic efficiency can be demonstrated. Moreover, since little detrimental materials are exhausted during the synthesis process of the catalyst structure according to the present invention, the synthesis process may be referred to as an environmentally friendly process. The durability of the synthesized catalyst structure is also improved.
[0166] In addition, according to the present invention, as illustrated in
[0167] In addition, since the one or two layers of carbon shells are piled by the one-step process to synthesize the nanostructured catalyst particles, the nanostructured catalyst particles can be deposited one on the other.
[0168] It is determined whether additional treatment, including coating/doping treatment, heat treatment or oxidation/reduction treatment, is (S11).
[0169] The additional treatment may be performed immediately after the reaction is completed in the high-temperature high-pressure closed reactor including the acquired catalyst structure. However, the additional treatment may also be performed in a general reactor for normal treatment after the resultant product is acquired.
[0170] Oxidation treatment/reduction treatment may further be performed on the acquired catalyst structure (S12-1). The oxidation treatment may be performed with a stream of air or oxygen while the acquired catalyst structure is maintained at a temperature higher than 200° C. and lower than 600° C. The oxidation treatment may be performed in substantially the same manner as in step S9.
[0171] In some cases, reduction treatment may further be performed on the acquired catalyst structure (S12-1). The reduction treatment may be performed in substantially the same manner as in step S9.
[0172] Heat treatment (S12-2) may be performed to increase crystallinity of the catalyst structure.
[0173] The heat treatment (S12-2) may be performed using an inert gas, a mixed gas of an inert gas and hydrogen, a mixed gas of an inert gas and a gaseous hydrocarbon gas, or a mixed gas of an inert gas and a nitrogen-containing gas.
[0174] The heat treatment (S12-2) may be performed at a temperature in the range of approximately 900° C. to approximately 1300° C. for approximately 1 to 6 hours in an inert gas atmosphere under an atmospheric pressure. When the heat treatment is performed at a temperature lower than 900° C., a noticeable effect exerted by performing the heat treatment cannot be expected, and when the heat treatment is performed at a temperature higher than 1300° C., deformation of the catalyst structure may be aggravated. When the catalyst structure includes an oxide, the carbon shell may be removed by a reaction between the oxide and the carbon shell.
[0175] In addition, coating/doping treatment may further be performed on the acquired catalyst structure (S12-3). The coating/doping treatment may be performed by supplying a material to be coated/doped into a closed reactor while the acquired catalyst structure is maintained at a temperature higher than 200° C. and lower than 600° C. The coating/doping treatment (S12-3) may be performed in a high-temperature high-pressure closed reactor through the same process steps with steps S2 to S11.
[0176] For example, N-doping may be performed on the nanostructured catalyst particles or the carbon shell, after supplying ammonia gas at approximately 500° C. or supplying ammonia gas with a nitrogen (N) containing source into the reactor. Additionally, boron (B), phosphorus (P), vanadium (V), molybdenum (Mo), etc. may also be doped in a similar manner. The doping treatment may be performed for approximately 1 to 2 hours. Doping temperatures may vary according to the source supplied for doping. However, when the doping temperature is maintained at a temperature of 200° C. or below, a doping reaction may not be sufficiently performed. When the doping temperature is maintained at a temperature of 600° C. or higher, agglomeration of the nanostructured catalyst particles may be accelerated due to the high temperature.
[0177] The catalyst structure prepared by the embodiments may be applied to various catalyst field and nanomaterial field, e.g., fuel cell, reverse electrodialysia, electrodialysis for desalination, hydrogen evolution reaction, catalysts for electrochemistry, batteries, catalysts for reformer, and photocatalysts.
[0178] The following experimental examples and figures are provided for a better understanding of conceptual aspects and methods of embodiments of the present invention and detailed descriptions of functions and effects of the present invention. However, the following Experimental Examples are provided by way of illustration and are not intended to be limiting the scope of the present invention.
[0179] Unless conditions of an internal reactor atmosphere gas before sealing are specified otherwise in the following examples, the expression “atmosphere gas before sealing” is used to mean an inert gas.
Experimental Example 1
[0180] A glassy carbon sphere having a diameter of approximately 200 nm as a 0-dimensional support and trimethy(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 15 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the carbon sphere support was acquired.
[0181]
[0182] It was confirmed from
Experimental Example 2
[0183] Multi-walled carbon nanotubes having a diameter of approximately 10 nm to approximately 20 nm and a length of 5 μm as a 1-dimensional support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 15 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the carbon nanotube support was acquired.
[0184]
[0185] Meanwhile, the catalyst structure was acquired by varying the elevated temperature to 600° C. while the other conditions were constantly maintained.
[0186] It was confirmed from
Experimental Example 3
[0187] Graphenes spheres having a thickness of approximately 1.6 nm and a diameter of approximately 5 μm and constructed in a layered structure having 1 to 3 layers as a 2-dimensional support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 20 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the graphene support was acquired.
[0188] Meanwhile, the catalyst structure was acquired by varying the elevated temperature to 600° C. while the other conditions were constantly maintained.
[0189] It was confirmed from
Experimental Example 4
[0190] Approximately 1.5 nm thick and approximately 5 μm sized N-doped graphenes spheres having a layered structure of 1 to 3 layers as a 2-dimensional support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 20 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the N-doped graphene support was acquired.
Experimental Example 5
[0191] Graphitized mesoporous carbon nanoparticles having a diameter of approximately 500 nm or less as a support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 15 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in a mesoporous carbon nanoparticle support was acquired.
[0192] Meanwhile, the catalyst structure was acquired by varying the elevated temperature to 600° C. while the other conditions were constantly maintained.
[0193] It was confirmed from
Experimental Example 6
[0194] Carbon black having a diameter of approximately 50 nm or less as a support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 20 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in a carbon black support was acquired.
[0195] Meanwhile, the catalyst structure was acquired by varying the elevated temperature to 600° C. while the other conditions were constantly maintained.
[0196] It was confirmed from
Experimental Example 7
[0197] 100 nm sized Cu/N doped carbon core/shell including a 20 nm thick N doped carbon shell as a support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 15 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in Cu/N doped carbon core/shell was acquired.
[0198]
Experimental Example 8
[0199] A 100 nm sized Fe.sub.3O.sub.4/N doped carbon core/shell including a 20 nm thick N doped carbon shell as a support and trimethyl(methylcyclopentadienyl)Pt(IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 15 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the Fe.sub.3O.sub.4/N doped carbon core/shell was acquired.
[0200]
Experimental Example 9
[0201] A catalyst structure having Pt nanostructured catalyst particles dispersed in a carbon sphere support was acquired in the same manner as in Experimental Example 1, except that Pt metal content became 50 wt %, based on the total weight of the catalyst structure.
[0202] It was confirmed from
Experimental Example 10
[0203] A catalyst structure having Pt nanostructured catalyst particles dispersed in a carbon sphere support was acquired in substantially the same manner as in Experimental Example 1, except that only synthesis temperatures were varied to 200° C., 300° C., 400° C., 500° C., and 600° C., as listed in Table 1, followed by measuring sizes (diameters) of Pt nanostructured catalyst particles.
TABLE-US-00001 TABLE 1 Experimental Pt nanoparticle Example Synthesis temperature (° C.) size (nm) 10-1 200 Less than 1.0 nm 10-2 300 1.0~1.5 nm 10-3 400 1.5 nm 10-4 500 1.5~2.0 nm 10-5 600 2.0 nm
[0204]
Experimental Example 11
[0205] As listed in Table 2, a catalyst structure having Pt nanostructured catalyst particles dispersed in a carbon sphere support was acquired in substantially the same manner as in Experimental Example 3, except that amounts of Pt based catalyst sources were varied to 10 wt %, 20 wt %, and 70 wt %, followed by measuring dispersion densities of the Pt nanostructured catalyst particles.
TABLE-US-00002 TABLE 2 Content of Pt based catalyst Experimental Example source (wt %) Dispersion density 11-1 10 Low 11-2 20 Intermediate 11-3 70 High
[0206]
Experimental Example 12
[0207] In order to investigate whether Pt nanostructured catalyst particles of a catalyst structure can be coated with an N-doped carbon shell, the catalyst structure was synthesized by N-doping using different conditions listed in Table 3 below. An N-doped catalyst structure was acquired by allowing the reaction to take place using pyridine (C.sub.5H.sub.5N) as an N-doped carbon shell source at a synthesis temperature of 600° C. for 1 hour.
TABLE-US-00003 TABLE 3 Content of Reactor volume: Pt based Content of Experimental catalyst N-doped carbon Example Support source (wt %) shell source (vol %) 12-1 Carbon spheres 15 1:0.01 12-2 Carbon black 15 1:0.01 12-3 Graphitized 15 1:0.01 mesoporous carbon 12-4 Carbon nanotubes 15 1:0.01 12-5 Graphenes 15 1:0.01
[0208]
Experimental Example 13
[0209] A glassy carbon sphere having a diameter of approximately 200 nm as a support and platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 15 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the carbon sphere support was acquired.
[0210]
Experimental Example 14
[0211] Multi-walled carbon nanotubes having a diameter of approximately 10 nm to approximately 20 nm and a length of 5 μm as a support and ruthenium (III) acetylacetonate (Ru(C.sub.5H.sub.7O.sub.2).sub.3) as a Ru based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Ru metal content became 10 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Ru nanostructured catalyst particles dispersed in the carbon nanotube support was acquired.
[0212]
Experimental Example 15
[0213] A glassy carbon sphere having a diameter of approximately 200 nm as a support and methylcyclopentadienyl(1,5-cyclooctadien)iridium(I) (C.sub.14H.sub.19Ir) as an Ir based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Ir metal content became 10 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Ir nanostructured catalyst particles dispersed in the carbon sphere support was acquired.
[0214]
Experimental Example 16
[0215] In order to investigate whether catalyst structures can be produced in the same manner as in the case of a transition metal, the catalyst structures having nanostructured catalyst particles dispersed in a carbon sphere support were acquired in substantially the same manner as in Experimental Example 1, except that only transition metal catalyst sources are varied under the conditions listed in Table 4 below.
TABLE-US-00004 TABLE 4 Transition metal catalyst source Experimental Example (Metal content, wt %) 16-1 Ferrocene (C.sub.10H.sub.10Fe) (15 wt %) 16-2 Cobaltocene (C.sub.10H.sub.10Co) (15 wt %) 16-3 Nickelocene (C.sub.10H.sub.10Ni) (10 wt %)
[0216]
[0217]
[0218]
Experimental Example 17
[0219] In order to investigate effects of a transition metal source (precursor) depending on the change in the content of Ferrocene as an Fe catalyst source, the catalyst structures having Fe nanoparticles dispersed in a carbon sphere support were acquired in substantially the same manner as in Experimental Example 16-1, except that the content of Ferrocene as the Fe catalyst source was varied to 5 wt %, 10 wt % and 15 wt %, followed by measuring dispersion densities of Fe nanostructured catalyst particles.
[0220]
Experimental Example 18
[0221] In order to investigate whether a catalyst structure having transition metal oxide nanoparticles dispersed in the support can be produced by oxidizing a transition metal from the catalyst structure having transition metal nanoparticles, catalyst structures were primarily synthesized in substantially the same manner as in Experimental Examples 16-1 to 16-3, oxidation reactions of the respective synthesized catalyst structures were allowed to take place under the conditions listed in Table 5.
TABLE-US-00005 TABLE 5 Transition metal Oxidation Oxidation Experimental catalyst source temperature reaction time Example (Metal content, wt %) (° C.) (Hr) 18-1 Ferrocene (C.sub.10H.sub.10Fe) 300° C. in air 1 (15 wt %) 18-2 Cobaltocene (C.sub.10H.sub.10Co) 300° C. in air 1 (15 wt %) 18-3 Nickelocene (C.sub.10H.sub.10Ni) 400° C. in air 1 (15 wt %)
Experimental Example 18
[0222]
TABLE-US-00006 TABLE 6 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % O K series 1.45493 1.00 26.13 1.26 55.25 Fe K series 1.21448 1.00 73.87 1.26 44.75 Total 100.00 100.00
[0223]
TABLE-US-00007 TABLE 7 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % O K series 1.45493 1.00 29.05 0.69 59.79 Co K series 1.28630 1.00 70.95 0.69 40.21 Total 100.00 100.00
[0224]
TABLE-US-00008 TABLE 8 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % O K series 1.45493 1.00 21.05 0.61 50.79 Ni K series 1.29311 1.00 79.95 0.61 49.21 Total 100.00 100.00
Experimental Example 19
[0225] A catalyst structure having Pt based binary alloy nanostructured catalyst particles dispersed in a support was synthesized in the following manner. A glassy carbon sphere having a diameter of approximately 200 nm as a support and first and second catalyst sources as catalyst sources were supplied into a reactor under room temperature and atmospheric pressure conditions, as listed in Table 9. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, the catalyst structure was acquired.
TABLE-US-00009 TABLE 9 Experimental First catalyst source Second catalyst source Example (Metal content, wt %) (Metal content, wt %) 19-1 Ir catalyst source: Pt based catalyst source: (methylcyclopentadienyl Trimethyl- (1,5-cyclooctadien)Ir) (methylcyclopentadienyl)Pt (10 wt %) (10 wt %) 19-2 Ru catalyst source: Pt based catalyst source: (Ru acetylacetonate) Trimethyl- (10 wt %) (methylcyclopentadienyl)Pt (10 wt %) 19-3 Ru catalyst source: Pt based catalyst source: (Ru acetylacetonate) Pt acetylacetonate (15 wt %) (20 wt %)
[0226]
[0227]
[0228]
TABLE-US-00010 TABLE 10 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ru K series 10.71255 1.00 41.97 2.79 58.26 Pt L series 2.75544 1.00 58.03 2.79 41.74 Total 100.00 100.00
Experimental Example 20
[0229] A catalyst structure having Pt based binary alloy nanostructured catalyst particles dispersed in the support was synthesized. A glassy carbon sphere having a diameter of approximately 200 nm as a support and first and second catalyst sources as catalyst sources were supplied into a reactor under room temperature and atmospheric pressure conditions, as listed in Table 11. The catalyst structure was basically synthesized by the same manner as described in Experimental Example 1 and the catalyst structure was acquired using different conditions listed in Table 11.
TABLE-US-00011 TABLE 11 Second catalyst Synthesis Experimental First catalyst source source (Metal temperature and Example Support (Metal content, wt %) content, wt %) time (° C., hr) 20-1 Multi-walled Pt based catalyst source: Fe catalyst source: 300° C., 1 hr carbon trimethyl(methylcyclopentadienyl) Ferrocene nanotubes Pt (10 wt %) (10 wt %) 20-2 Carbon Pt based catalyst source: Fe catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Ferrocene (18 wt %) (10 wt %) 20-3 Carbon Pt based catalyst source: Fe catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Fe acetylacetonate (18 wt %) (10 wt %) 20-4 Multi-walled Pt based catalyst source: Co catalyst source: 300° C., 1 hr carbon trimethyl Cobaltocene nanotubes (methylcyclopentadienyl) (10 wt %) Pt (10 wt %) 20-5 Carbon Pt based catalyst source: Co catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Cobaltocene (18 wt %) (10 wt %) 20-6 Carbon Pt based catalyst source: Co catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Co acetylacetonate (18 wt %) (10 wt %) 20-7 Multi-walled Pt based catalyst source: Ni catalyst source: 300° C., 1 hr carbon Trimethyl Nickelocene nanotubes (methylcyclopentadienyl) (10 wt %) Pt (10 wt %) 20-8 Carbon Pt based catalyst source: Ni catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Nickelocene (15 wt %) (15 wt %) 20-9 Carbon Pt based catalyst source: Ni catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Ni acetylacetonate (18 wt %) (10 wt %) 20-10 Carbon Pt based catalyst source: Mn catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Mn acetylacetonate (20 wt %) (3 wt %) 20-11 Carbon Pt based catalyst source: Cu catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Cu acetylacetonate (20 wt %) (18 wt %) 20-12 Carbon Pt based catalyst source: Sn catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Sn acetylacetonate (20 wt %) (3 wt %) 20-13 Carbon Pt based catalyst source: Ga catalyst source: 350° C., 1 hr spheres Pt acetylacetonate Ga acetylacetonate (25 wt %) (5 wt %)
[0230]
[0231]
TABLE-US-00012 TABLE 12 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Fe K series 1.21448 1.00 8.68 0.52 24.93 Pt L series 2.75544 1.00 91.32 0.52 75.07 Total 100.00 100.00
[0232]
TABLE-US-00013 TABLE 13 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Fe K series 1.21448 1.00 8.74 0.83 25.08 Pt L series 2.75544 1.00 91.26 0.83 74.92 Total 100.00 100.00
[0233]
[0234]
TABLE-US-00014 TABLE 14 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Co K series 1.28630 1.00 9.63 0.71 26.07 Pt L series 2.75544 1.00 90.37 0.71 73.93 Total 100.00 100.00
[0235]
TABLE-US-00015 TABLE 15 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Co K series 1.28630 1.00 8.32 0.99 23.11 Pt L series 2.75544 1.00 91.68 0.99 76.89 Total 100.00 100.00
[0236]
[0237]
TABLE-US-00016 TABLE 16 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ni K series 1.29311 1.00 19.01 0.73 43.83 Pt L series 2.75544 1.00 80.99 0.73 56.17 Total 100.00 100.00
[0238]
TABLE-US-00017 TABLE 17 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ni K series 1.29311 1.00 14.49 0.99 36.02 Pt L series 2.75544 1.00 85.51 0.99 63.98 Total 100.00 100.00
[0239]
TABLE-US-00018 TABLE 18 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Mn K series 1.19711 1.00 3.48 0.49 12.51 Pt L series 2.75544 1.00 96.52 0.49 87.49 Total 100.00 100.00
[0240]
TABLE-US-00019 TABLE 19 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Cu K series 1.42103 1.00 51.86 0.71 76.78 Pt L series 2.75544 1.00 48.14 0.71 23.22 Total 100.00 100.00
TABLE-US-00020 TABLE 20 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Cu K series 1.42103 1.00 61.11 0.84 82.83 Pt L series 2.75544 1.00 38.89 0.84 17.17 Total 100.00 100.00
[0241]
TABLE-US-00021 TABLE 21 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Sn K series 33.89798 1.00 4.34 8.44 6.94 Pt L series 2.75544 1.00 95.66 8.44 93.06 Total 100.00 100.00
TABLE-US-00022 TABLE 22 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Sn K series 33.89798 1.00 100.00 0.00 100.00 Total 100.00 100.00
[0242]
TABLE-US-00023 TABLE 23 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ga K series 1.64918 1.00 3.45 0.68 9.10 Pt L series 2.75544 1.00 96.55 0.68 90.90 Total 100.00 100.00
Experimental Example 21
[0243] Catalyst structures having multi-component alloy nanostructured catalyst particles dispersed in a support were synthesized in the following manner. The catalyst structures are basically synthesized in substantially the same manner as in Experimental Example 1 using various catalyst sources under different conditions listed in Table 24.
TABLE-US-00024 TABLE 24 Experimental Example Catalyst source (Metal content, wt %) 21-1 Pt acetylacetonate (85 wt %) Fe acetylacetonate (7 wt %) Co acetylacetonate (3 wt %) Ni acetylacetonate (5 wt %) 21-2 Pt acetylacetonate (87 wt %) Ferrocene (5 wt %) Co acetylacetonate (4 wt %) Ni acetylacetonate (5 wt %) 21-3 Pt acetylacetonate (35 wt %) Co acetylacetonate (40 wt %) Cr acetylacetonate (25 wt %) 21-4 Pt acetylacetonate (45 wt %) Co acetylacetonate (39 wt %) V acetylacetonate (16 wt %) 21-5 Pt acetylacetonate (75 wt %) Co acetylacetonate (20 wt %) Ni acetylacetonate (5 wt %) 21-6 Pt acetylacetonate (85 wt %) Fe acetylacetonate (7 wt %) Co acetylacetonate (3 wt %) 21-7 Pt acetylacetonate (85 wt %) Fe acetylacetonate (7 wt %) Ni acetylacetonate (5 wt %)
[0244]
[0245]
[0246]
[0247]
[0248]
[0249]
[0250]
Experimental Example 22
[0251] Catalyst structures having organometallic nanostructured catalyst particles dispersed in the support were synthesized in the following manner. The catalyst structures were basically synthesized by the same manner as described in Experimental Example 2 in which multi-walled carbon nanotubes were used. Here, the catalyst structures were acquired using different catalyst sources listed in Table 25 at a reaction temperature of 450° C. for 1 hour.
TABLE-US-00025 TABLE 25 Experimental Example Catalyst source (Metal content, wt %) 22-1 Iron (II) phthalocyanine, C.sub.32H.sub.16FeN.sub.8) (10 wt %) 22-2 Cobalt (II) phthalocyanine (C.sub.32H.sub.16CoN.sub.8) (10 wt %) 22-3 Manganese (II) phthalocyanine (C.sub.32H.sub.16MnN.sub.8) (10 wt %)
[0252]
[0253]
[0254]
Experimental Example 23
[0255] Carbon nanotubes having a diameter of approximately 10 nm to approximately 20 nm and a length of 5 μm coated with Fe—N doped carbon as a support and trimethyl(methylcyclopentadienyl)Pt(IV) (C5H4CH3Pt(CH3)3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content became 10 wt %, based on the total weight of the catalyst structure. The carbon nanotubes coated with Fe—N coped carbon were prepared by thermally treating the multi-walled carbon nanotubes treated with iron phorphyrine (C20H14FeN4) at 900° C. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 300° C., followed by allowing the reaction to take place for 1 hour. After the reaction was completed, the reactor was cooled back to room temperature. If the temperature of the reactor is cooled down to room temperature, a pressure control valve was slowly opened to reduce the internal pressure of the reactor to room temperature. Thereafter, a catalyst structure having Pt nanostructured catalyst particles dispersed in the carbon nanotube support was acquired.
[0256]
Experimental Example 24
[0257] As a catalyst structure having nanostructured catalyst particles dispersed in the support was synthesized using non-carbon based supports. The catalyst structure was basically synthesized by the same manner as described in Experimental Example 1 in which trimethyl(methylcyclopentadienyl)Pt was used as a Pt based catalyst source. Here, the catalyst structure was acquired using different supports and different conditions listed in Table 26.
TABLE-US-00026 TABLE 26 Synthesis Catalyst source temperature Experimental (Metal content, and time Example Support wt %) (° C., hr) 24-1 Al2O3 particles 15 wt % 350° C., 1 hr (Diameter: 50~100 nm) 24-2 CaAl2O4 particles 40 wt % 300° C., 1 hr (Diameter: 1~2 μm) 24-3 Si particles 20 wt % 350° C., 1 hr 24-4 Apatite nanoparticles 20 wt % 350° C., 1 hr
[0258]
[0259]
[0260]
[0261]
Experimental Example 25
[0262] A catalyst structure having Pt-transition metal based binary alloy nanostructured catalyst particles dispersed in the support was synthesized using non-carbon based supports. The catalyst structure was basically synthesized by the same manner as described in Experimental Example 1 in which trimethyl(methylcyclopentadienyl)Pt was used as a Pt based catalyst source. Here, the catalyst structure was acquired using different conditions listed in Table 27.
TABLE-US-00027 TABLE 27 Synthesis Experimental First catalyst source Second catalyst source temperature and Example Support (Metal content, wt %) (Metal content, wt %) time (° C., hr) 25-1 Al.sub.2O.sub.3 particles Pt based catalyst Fe catalyst source: 350° C., 1 hr (Diameter: 10 nm) source: Ferrocene Pt acetylacetonate (10 wt %) (18 wt %) 25-2 SiO.sub.2 particles Pt based catalyst Fe catalyst source: 350° C., 1 hr (Diameter: 20 nm) source: Ferrocene Pt acetylacetonate (10 wt %) (18 wt %) 25-3 CeO.sub.2 particles Pt based catalyst Fe catalyst source: 350° C., 1 hr (Diameter: 50 nm) source: Fe acetylacetonate Pt acetylacetonate (10 wt %) (18 wt %) 25-4 SnO.sub.2 particles Pt based catalyst Fe catalyst source: 350° C., 1 hr (Diameter >100 nm) source: Fe acetylacetonate Pt acetylacetonate (10 wt %) (18 wt %) 25-5 ZnO particles Pt based catalyst Fe catalyst source: 350° C., 1 hr (Diameter >100 nm) source: Ferrocene Pt acetylacetonate (10 wt %) (18 wt %)
[0263]
[0264]
TABLE-US-00028 TABLE 28 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % O K series 1.45493 1.00 6.96 0.42 31.71 Si K series 1.00000 1.00 12.09 0.52 31.37 Fe K series 1.21448 1.00 7.15 0.40 9.34 Pt L series 2.75544 1.00 73.80 0.82 27.57 Total 100.00 100.00
[0265]
TABLE-US-00029 TABLE 29 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % C K series 3.11489 1.00 2.59 0.57 11.20 O K series 1.45493 1.00 18.53 0.52 60.12 Fe K series 1.21448 1.00 1.27 0.18 1.18 Ce L series 2.06031 1.00 65.74 0.84 24.35 Pt L series 2.75544 1.00 11.87 0.71 3.16 Total 100.00 100.00
[0266]
TABLE-US-00030 TABLE 30 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % C K series 3.11489 1.00 3.21 0.46 27.65 O K series 1.45493 1.00 0.38 0.16 2.44 Fe K series 1.21448 1.00 1.13 0.20 2.09 Sn K series 33.89798 1.00 50.48 3.26 44.04 Pt L series 2.75544 1.00 44.80 2.99 23.78 Total: 100.00 100.00
[0267]
TABLE-US-00031 TABLE 31 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Fe K series 1.21448 1.00 9.88 0.84 27.69 Pt L series 2.75544 1.00 90.12 0.84 72.31 Total: — — — 100.00 — 100.00
Experimental Example 26
[0268]
[0269] In order to measure ORR performance and electrochemical properties, approximately 1 to 2 mg of a catalyst was immersed in a solution of NAFION (trade name by DuPont) mixed with alcohol to then be ultrasonically dispersed. Ink was prepared and coated on a surface of a glassy carbon (GC) support using a pipette. A catalyst electrode was prepared and dried using an infrared (IR) lamp. Electrochemical properties of the catalysts were measured using a potentiostat. The ORR measurement was carried out in a 0.1M HClO.sub.4 solution at 1,600 rpm. ORR polarization curves were measured at an anodic sweep rate of 10 mV/s in a specific electric potential range of 0.0 V to 1.2 V (versus a reverse hydrogen electrode (RHE)). The measurement was carried out at room temperature.
TABLE-US-00032 TABLE 32 Pt I.sub.k @ Specific Mass loading ECSA 0.9 Activity Activity E.sub.1/2 Catalyst (ug/cm.sup.2) (m.sup.2/g.sub.Pt) (mA/cm.sup.2) (uA/cm.sup.2) (A/mg.sub.Pt) (mV) CS300 15 165.51 0.852 100.9 0.03 789 CNT300 15 322.84 1.986 120.6 0.08 833 CNG300 15 248.29 3.132 247.2 0.13 877 Common 20 107.97 1.447 262.7 0.07 857 20% Pt/C
[0270] In Table 32, CS300 refers to a catalyst having Pt nanoparticles dispersed in a carbon sphere support, CNT300 refers to a catalyst having Pt nanoparticles dispersed in a carbon nanotube support, and CNG300 refers to a catalyst having Pt nanoparticles dispersed in a graphitized mesoporous carbon nanoparticle support.
[0271] As confirmed from the graphs illustrated in
Experimental Example 27
[0272] In this embodiment, ORR performance and electrochemical properties of Pt/carbon sphere catalysts with loading of 37% Pt were measured. Measurement results of long-term oxygen reduction reaction (ORR) performance of the Pt based catalysts including carbon spheres are shown in
TABLE-US-00033 TABLE 33 Accelerated CS Pt Surface @ Specific Mass Durability Test loading loading Area 0.9 V Activity Activity /2 (ADT) (ug/cm.sup.2) (ug/cm.sup.2) (m.sup.2/g.sub.Pt) (mA/cm.sup.2) (uA/cm.sup.2) (A/mg.sub.Pt) (V) Fresh 10 3.7 152 03 5 16 868 k cycles 34 33 1 18 873 (0.6-1.0 V) 0k cycles 16 34 3 18 871 (0.6-1.0 V) 5k cycles 8 57 4 14 860 (0.3-1.0 V) 0k cycles 7 36 3 12 853 (0.6-1.0 V) 0k cycles 3 80 4 15 862 (0.6-1.0 V) 0k cycles 9 86 0 15 863 (0.6-1.0 V) 0k cycles 6 62 9 14 858 (0.6-1.0 V)
[0273] In Table 33, “Fresh” indicates initial catalytic performance, “ADT_5k” indicates catalytic performance after 5,000 cycles and “ADT_50k” indicates catalytic performance after 50,000 cycles, in accelerated durability tests.
[0274] The graphs illustrated in
Experimental Example 28
[0275] The dispersion density was measured from the TEM and STEM results and calculated by measuring the number of nanoparticles coated per 100 nm.sup.2. As illustrated, the reactions were carried out at temperatures in the range of 200° C. to 600° C. and catalyst sources were supplied such that the Pt metal content became approximately 10 wt %, 20 wt %, 30 wt %, 40 wt %, and 50 wt %. Average particle sizes of Pt nanoparticles were 1.0 nm, 1.25 nm, 1.5 nm, 1.75 nm, and 2.0 nm at temperatures of 200° C., 300° C., 400° C., 500° C., and 600° C., respectively.
[0276]
[0277] When the synthesis temperature is 300° C., the dispersion density of 1.25 nm sized Pt nanoparticles for the surface area (SA) of the support will now be described. That is to say, the coating areas of Pt nanoparticles corresponding to approximately 10% or greater of the surface area of the support for all of the contents are calculated. In more detail, when the Pt metal content is 10 wt %, the coating area of Pt nanoparticles corresponding to approximately 62% of the surface area of the support is calculated. When the Pt metal content is 20 wt %, the coating area of Pt nanoparticles corresponding to a relatively large area, e.g., approximately 115% of the surface area of the support, is calculated. When the Pt metal content is in the maximum level, i.e., 50 wt %, the coating area of Pt nanoparticles corresponding to an area of 2.8 times the surface area of the support, is calculated. This means that Pt nanoparticles are stacked on carbon shells and then coated while being continuously stacked on the surface of the support without agglomeration, as confirmed from the TEM or STEM images in various embodiments of the present invention.
Experimental Example 29
[0278] Sizes of the nanostructured catalyst particles were calculated by measuring diameters of nanoparticles based on measurement results by TEM and STEM. That is to say, the sizes of the nanostructured catalyst particles were calculated by measuring the number of nanoparticles corresponding to the diameters of Pt nanoparticles coated on carbon spheres. The reaction temperatures were varied to 300° C., 400° C., 500° C., and 600° C., and catalyst sources were supplied such that the Pt metal content became approximately 10 wt %.
Experimental Example 30
[0279] Carbon black having a diameter of approximately 50 nm a support, platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and cobalt (II) acetylacetonate (CoC.sub.10H.sub.14O.sub.4) as a Co based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt metal content and Co metal content become 40 wt % and 5 wt %, respectively, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 30 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor (S7). Thereafter, in order to remove impurities remaining on surfaces of nanoparticles, oxidation treatment was first performed at the same temperature as the elevated reaction temperature (i.e., 350° C.) and reduction treatment was then performed (S9). Finally, the temperature was lowered to room temperature under an inert gas atmosphere, acquiring a sample (S10).
[0280]
[0281] Table 34 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include Pt.sub.3Co nanoparticles. It is also confirmed that XRD analysis results of crystallographic structures are identical with EDX analysis results.
TABLE-US-00034 TABLE 34 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Co K series 1.28630 1.00 8.41 1.52 23.31 Pt L series 2.75544 1.00 91.59 1.52 76.69 Total — 100.00 100.00
Experimental Example 31
[0282] A catalyst structure was synthesized at different post treatment temperatures of oxidation/reduction treatment, corresponding to S9, that is, 350° C., 450° C. and 550° C., while maintaining the precursor and support used and other reaction steps to be same as in Experimental Example 30. The measurement results are illustrated in
[0283] When the acquired catalyst structure was synthesized at 350° C., 1.8 to 2.2 nm sized catalyst nanoparticles were identified, and when the acquired catalyst structure was synthesized at 450° C., 2.3 to 2.7 nm sized catalyst nanoparticles were identified, from which it was confirmed that sizes of the catalyst nanoparticles were gradually increased as the reaction temperature was elevated.
Experimental Example 32
[0284] A catalyst structure was synthesized using the same precursor and support as in Experimental Example 30, except for reaction steps. That is to say, after the reactor was perfectly sealed and the reaction temperature was elevated to reach 350° C., the reaction was allowed to be carried out for 30 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor (S7) and the reactor was cooled to room temperature. Thereafter, the temperature of the reactor was again elevated up to 350° C. and oxidation treatment was then performed while maintaining the reactor temperature at 350° C. Then, the reactor temperature was further elevated up to 700° C. and reduction treatment was then performed while maintaining the reactor temperature at 700° C. Finally, the temperature was lowered to room temperature under an inert gas atmosphere, acquiring a sample. The measurement results are illustrated in
[0285]
[0286] Table 35 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include Pt.sub.3Co nanoparticles. It is also confirmed that XRD analysis results of crystallographic structures are identical with EDX analysis results.
TABLE-US-00035 TABLE 35 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Co K series 1.28630 1.00 8.08 0.18 22.54 Pt L series 2.75544 1.00 91.92 0.18 77.46 Total — 100.00 100.00
Experimental Example 33
[0287] A catalyst structure was synthesized using the same precursor and support as in Experimental Example 30, except for internal atmosphere conditions of a reactor that has yet to be sealed. That is to say, the catalyst structure was acquired under different internal atmosphere conditions of the reactor, as listed in Table 36 below. The measurement results are illustrated in
TABLE-US-00036 TABLE 36 Internal atmosphere conditions of a FIG. 78 reactor that has yet to be sealed (4 atm) (a) 100% oxygen (b) 5% oxygen contained in argon gas (c) 100% argon
[0288]
Experimental Example 34
[0289] A catalyst structure was synthesized using the same precursor and support as in Experimental Example 30, while supplying platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and ruthenium (III) acetylacetonate (Ru(C.sub.5H.sub.7O.sub.2).sub.3) as a Ru based catalyst source (precursor).
[0290]
Experimental Example 35
[0291] Carbon black having a diameter of approximately 50 nm as a support, platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor), cobalt (III) acetylacetonate (Co(C.sub.5H.sub.7O.sub.2).sub.3) as a Co based catalyst source (precursor), and bis(acetylacetonato) dioxomolybdenum(VI) ([CH.sub.3COCH═C(O—)CH.sub.3].sub.2MoO.sub.2) as a Mo based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt, Co and Mo metal contents became 40 wt %, 5 wt % and 0.5 wt %, respectively, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 30 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, oxidation treatment was first performed at the same temperature as the elevated reaction temperature (i.e., 350° C.) and reduction treatment was then performed. Finally, the temperature was lowered to room temperature under an inert gas atmosphere, acquiring a sample.
[0292]
[0293] Table 37 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include Pt.sub.3CoMo.sub.0.2 nanoparticles.
TABLE-US-00037 TABLE 37 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Co K series 1.28630 1.00 9.82 0.28 25.95 Mo K series 7.38599 1.00 2.50 0.56 4.05 Pt L series 2.75544 1.00 87.68 0.58 70.00 Total — 100.00 100.00
Experimental Example 36
[0294] Carbon black having a diameter of approximately 50 nm as a support, platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and cobalt (II) acetylacetonate (CoC.sub.10H.sub.14O.sub.4) as a Co based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt and Co metal contents became 40 wt % and 5 wt %, respectively, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 30 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, oxidation treatment was first performed at the same temperature as the elevated reaction temperature (i.e., 350° C.) and reduction treatment was then performed. Finally, the temperature was lowered to room temperature under an inert gas atmosphere, acquiring a sample.
[0295] Next, hexacarboxyl molybdenum (Mo(CO).sub.6) as a Mo based catalyst source (precursor) and a Pt based catalyst precursor were supplied into a closed reactor together with the acquired sample for further performing a sealing reaction. As the result, as illustrated in
[0296] Table 38 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include Pt.sub.3CoMo.sub.0.2 nanoparticles.
TABLE-US-00038 TABLE 38 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Co K series 1.28630 1.00 8.92 0.24 24.45 Mo K series 7.38599 1.00 0.12 0.42 0.21 Pt L series 2.75544 1.00 90.96 0.44 75.34 Total — 100.00 100.00
Experimental Example 37
[0297] Carbon black as a carbon support and hexacarboxyl molybdenum (Mo(CO).sub.6) and sulfur as a Mo based catalyst source (precursor) were supplied into a reactor, such that MoS.sub.2 content became 30 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 550° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, reaction temperature was lowered to room temperature, acquiring a catalyst structure including MoS.sub.2 nanoparticles dispersed in the carbon black support.
[0298]
Experimental Example 38
[0299] The catalyst structure acquired in Experimental Example 37 was put into a closed reactor and trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt precursor was added to the closed reactor, such that Pt content became 50 wt %, based on the total weight of the catalyst structure, for further performing a sealing reaction. Here, the reaction was allowed to take place for 30 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, reaction temperature was lowered to room temperature, acquiring a catalyst structure
[0300] As the result, as illustrated in
Experimental Example 39
[0301] Titanium (Ti) nanoparticles having a diameter of approximately 80 nm as a support and trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt content became 30 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0302] As illustrated in
[0303] Table 39 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include Pt nanoparticles.
TABLE-US-00039 TABLE 39 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ti K series 1.09006 1.00 0.66 0.12 2.64 Pt L series 2.75544 1.00 99.34 0.12 97.36 Total — 100.00 100.00
Experimental Example 40
[0304] Titanium (Ti) nanoparticles having a diameter of approximately 80 nm as a support, trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) and bis(ethylcyclopentadienyl) ruthenium (II) (C.sub.7H.sub.9RuC.sub.7H.sub.9) as a Ru based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that total catalyst content became 30 wt %. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0305] As illustrated in
[0306] Table 40 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the Pt.sub.3Ru nanoparticles.
TABLE-US-00040 TABLE 40 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ru K series 10.71255 1.00 15.07 6.04 25.52 Pt L series 2.75544 1.00 84.93 6.04 74.08 Total — 100.00 100.00
Experimental Example 41
[0307] Titanium (Ti) nanoparticles having a diameter of approximately 80 nm as a support, trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) and bis(ehtylcyclopentadiel) cobalt (II) (C.sub.7H.sub.9CoC.sub.7H.sub.9) as a Co based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that total catalyst content became 30 were supplied into a reactor under room temperature and atmospheric pressure conditions, such that total catalyst content became 30 wt %. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0308] As illustrated in
[0309] Table 41 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include 5 nm sized Pt.sub.3Co nanoparticles.
TABLE-US-00041 TABLE 41 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Ti K series 1.28630 1.00 3.77 0.09 11.62 Co K series 1.28630 1.00 8.92 0.13 22.42 Pt L series 2.75544 1.00 87.27 0.16 65.96 Total — 100.00 100.00
Experimental Example 42
[0310] Silicon (Si) nanoparticles having a diameter of approximately 80 nm as a support and trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt content became 30 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0311] As illustrated in
[0312] Table 42 demonstrates measurement results of atomic ratios of the acquired catalyst structure, as analyzed by EDX. Based on the measured atomic ratios, it can be deduced that the nanoparticles include Pt nanoparticles.
TABLE-US-00042 TABLE 42 Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Si K series 1.00000 1.00 80.04 0.90 80.81 O K series 1.45493 1.00 10.01 0.49 17.74 Pt L series 2.75544 1.00 9.95 0.88 1.45 Total — 100.00 100.00
Experimental Example 43
[0313] Silicon (Si) nanoparticles having a diameter of approximately 80 nm as a support, trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) and cobaltocene (C.sub.10H.sub.10Co) as a Co based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt content became 30 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0314] As illustrated in
Experimental Example 44
[0315] A catalyst structure was synthesized in the same manner as in Experimental Example 43 in view of the support used and reaction conditions while supplying cobalt (II) acetylacetonate (CoC.sub.10H.sub.14O.sub.4) as a Co based catalyst source (precursor), such that Co metal content became 30 wt %, based on the total weight of the catalyst structure.
[0316] As illustrated in
Experimental Example 45
[0317] Silicon (Si) nanoparticles having a diameter of approximately 80 nm as a support and cobaltocene (C.sub.10H.sub.10Co) as a Co based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Co content became 30 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 450° C. (
[0318] As illustrated in
Experimental Example 46
[0319] Zinc nanoparticles having a diameter of approximately 300 nm as a support, platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and ferrocene (C.sub.10H.sub.10Fe) as a Fe based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that metal contents became 30 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0320] As illustrated in
Experimental Example 47
[0321] Carbon sphere nanoparticles having a diameter of approximately 200 nm as a support and trimethyl(methylcyclopentadiel) platinum (IV) (C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3) as a Pt based catalyst source (precursor) were supplied into a reactor under room temperature and atmospheric pressure conditions, such that Pt content became 40 wt %, based on the total weight of the catalyst structure. The reactor was perfectly sealed and the temperature of the reactor was elevated up to 350° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the reaction temperature was lowered to room temperature, acquiring a sample.
[0322] As illustrated in
Experimental Example 48
[0323] A catalyst structure was synthesized using the same support, catalyst precursor and reaction conditions as in Experimental Example 47, while additionally supplying UREA (CH.sub.4N.sub.2O) for nitrogen (N) doping.
[0324] As illustrated in
Experimental Example 49
[0325] A catalyst structure was synthesized using the same support and reaction conditions as in Experimental Example 47, while supplying platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and ferrocene (C.sub.10H.sub.10Fe) as a Fe based catalyst source (precursor), such that Pt and Fe metal contents became 18 wt % and 10 wt %, respectively, based on the total weight of the catalyst structure.
[0326] As illustrated in
Experimental Example 50
[0327] A catalyst structure was synthesized using the same support and reaction conditions as in Experimental Example 47, while supplying platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and cobaltocene (C.sub.10H.sub.10Co) as a Co based catalyst source (precursor), such that Pt and Co metal contents became 18 wt % and 10 wt %, respectively, based on the total weight of the catalyst structure.
[0328] As illustrated in
Experimental Example 51
[0329] A catalyst structure was synthesized using the same support and reaction conditions as in Experimental Example 47, while supplying platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor) and nickel (II) acetylacetonate (NiC.sub.10H.sub.14O.sub.4), such that Pt and Co metal contents became 18 wt % and 10 wt %, respectively, based on the total weight of the catalyst structure.
[0330] As illustrated in
Experimental Example 52
[0331] A catalyst structure was synthesized using the same support and reaction conditions as in Experimental Example 47, while supplying platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor), ferrocene (C.sub.10H.sub.10Fe) as a Fe based catalyst source (precursor), cobalt (II) acetylacetonate (CoC.sub.10H.sub.14O.sub.4) as a Co based catalyst source (precursor), and nickel (II) acetylacetonate (NiC.sub.10H.sub.14O.sub.4), such that Pt and Co metal contents became 18 wt % and 10 wt %, respectively, based on the total weight of the catalyst structure.
[0332] As illustrated in
Experimental Example 53
[0333] A catalyst structure was synthesized using the same support and reaction conditions as in Experimental Example 52 using platinum (II) acetylacetonate (PtC.sub.10H.sub.14O.sub.4) as a Pt based catalyst source (precursor), ferrocene (C.sub.10H.sub.10Fe) as a Fe based catalyst source (precursor), cobalt (II) acetylacetonate (CoC.sub.10H.sub.14O.sub.4) as a Co based catalyst source (precursor), and nickel (II) acetylacetonate (NiC.sub.10H.sub.14O.sub.4). In detail, a sealing reaction was carried out using Pt and Fe precursors, acquiring a sample. The Pt and Fe precursors were supplied to the sample for additionally performing a sealing reaction. Thereafter, Pt and Ni precursors were supplied to a closed reactor together with the acquired sample to cause a reaction, thereby finally obtaining a sample.
[0334] As illustrated in
TABLE-US-00043 TABLE 43 (Red) Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Fe K series 1.21448 1.00 68.46 8.53 70.58 Co K series 1.28630 1.00 15.34 8.53 14.42 Ni K series 1.29311 1.00 16.30 0.00 15.58 Total — 100.00 100.00
TABLE-US-00044 TABLE 44 (Blue) Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Fe K series 1.21448 1.00 2.03 8.53 2.20 Co K series 1.28630 1.00 68.43 8.53 69.33 Ni K series 1.29311 1.00 29.54 0.00 28.47 Total — 100.00 100.00
TABLE-US-00045 TABLE 45 (Green) Ele- Line Absorption Wt % ment Type k factor Correction Wt % Sigma Atomic % Fe K series 1.21448 1.00 0.00 0.00 0.00 Co K series 1.28630 1.00 1.41 8.53 1.90 Ni K series 1.29311 1.00 98.59 8.53 98.10 Total — 100.00 100.00
[0335]
Experimental Example 54
[0336] In order to investigate whether catalyst nanoparticles dispersed in other types of supports can be synthesized, catalyst structures were acquired under various conditions listed in Table 46 below.
TABLE-US-00046 TABLE 46 Synthesis temperature First Second Total (° C.) and Exp. catalyst catalyst catalyst reaction time Example Support source source content (hr) Post treatment 54-1 Carbon felt C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3 20 wt % 350° C., 1 hr Inert gas supply stabilization 54-2 Metal (Cu, C.sub.5H.sub.4CH.sub.3Pt(CH.sub.3).sub.3 20 wt % 350° C., 1 hr Inert gas supply Ti, SUS) stabilization foil 54-3 Metal (Ti) PtC.sub.10H.sub.14O.sub.4 RuC.sub.15H.sub.21O.sub.6 30 wt % 350° C., 1 hr Inert gas supply foam stabilization 54-4 Metal (Ti) Mo(Co).sub.6 S (sulfur) 30 wt % 550° C., 1 hr Inert gas supply wire stabilization 54-5 Hexagonal PtC.sub.10H.sub.14O.sub.4 CoC.sub.10H.sub.14O.sub.4 30 wt % 350° C., 1 hr 1) Inert gas supply boron stabilization nitride 2) Oxidation (hBN) treatment at 350° C. while supplying inert gas and oxygen 3) Reduction treatment while supplying inert gas and hydrogen 4) Cooling down to room temperature while supplying inert gas and acquiring sample
[0337] Not only a carbon felt but also fiber paper, a foam or a foil can be used as a carbon support.
[0338] Any material selected from Cu, Ti and SUS can be used as a metal element for a foil and may be in a foam type or a wire type.
[0339] In
[0340] In
[0341]
[0342]
[0343]
Experimental Example 55
[0344] Carbon black nanoparticles (a), graphite nanoparticles (b), carbon sphere nanoparticles (c), carbon nanotubes (d), graphene (e), N-doped graphene (f) as carbon supports and hexacarboxyl molybdenum (Mo(CO).sub.6) and sulfur as Mo based catalyst sources were supplied into a reactor, such that MoS.sub.2 content became 50 wt %, based on the total weight of the catalyst structure acquired. Then, the reactor was perfectly sealed and the temperature of the reactor was elevated up to 500° C., followed by allowing the reaction to take place for 60 minutes. After the reaction was completed, the internal pressure of the reactor was eliminated and the reaction was stabilized while supplying an inert gas to then remove unreacted materials and byproducts from the reactor. Thereafter, the temperature was lowered to room temperature, acquiring the catalyst structure including MoS.sub.2 nanoparticles dispersed in the support.
[0345]
[0346] While exemplary embodiments of the present invention have been described in detail, the spirit and scope of the present invention are not limited to the foregoing embodiments and it will be appreciated by those skilled in the art that various modifications and improvements using the basic concept of the present invention defined in the appended claims are also included in the scope of the present