Patent classifications
B01J37/348
CATALYST AND METHODS FOR MAKING AND USING
A method for making a catalyst comprises providing an initial compound having a perovskite lattice structure according to formula I
M.sup.1M.sup.2M.sup.3O.sub.3 FORMULA I,
where M.sup.1 is about 1 relative elemental ratio strontium (Sr); M.sup.2 is from greater than 0 to 0.7 relative elemental ratio and is selected from cobalt (Co), scandium (Sc), iron (Fe), nickel (Ni), and titanium (Ti); and M.sup.3 is 0.3 to 0.6 relative elemental ratio iridium (Ir). Initial exemplary compounds include SrSc.sub.0.5Ir.sub.0.5O.sub.3 (SSI) and SrCo.sub.0.5Ir.sub.0.5O.sub.3 (SCI). M.sup.1 and/or M.sup.2 cations are selectively leached from the initial compound to produce a catalyst having substantially increased catalytic performance. Cycling SSI or SCI in an acid produces SSI-H or SCI-H; cycling SSI or SCI in a base produces SSI-OH or SCI-OH. Dual-site metal leaching induced catalytic activity improvement by about 2 orders of magnitude, making reconstructed SrCo.sub.0.5Ir.sub.0.5O.sub.3 among the best-known catalysts for water oxidation in an acidic condition.
LOW-PLATINUM CATALYST BASED ON NITRIDE NANOPARTICLES AND PREPARATION METHOD THEREOF
A low-platinum catalyst based on nitride nanoparticles and a preparation method thereof. A component of an active metal of the catalyst directly clades on a surface of nitride particles or a surface of nitride particles loaded on a carbon support in an ultrathin atomic layer form. Preparation steps including: preparing a transition-metal ammonia complex first, nitriding the obtained ammonia complex solid under an atmosphere of ammonia gas to obtain nitride nanoparticles; loading the nitride nanoparticles on a surface of a working electrode, depositing an active component on a surface of the nitride nanoparticles by pulsed deposition, to obtain the low platinum loading catalyst using a nitride as a substrate. The catalyst may be used as an anode or a cathode catalyst of a low temperature fuel cell.
PROCESS AND MATERIAL FOR GROWTH OF ADSORBED COMPOUND VIA NANOSCALE-CONTROLLED RESISTIVE HEATING AND USES THEREOF
Disclosed is a method for making a material having supported micro- and/or nanostructures, the method includes (a) obtaining a substrate comprising a precursor material and an electrically conductive layer of micro- or nanostructures embedded into at least a portion of a first surface of the substrate, and (b) applying a voltage across the electrically conductive layer to heat the micro- or nanostructures, wherein the heat converts the precursor material into micro- and/or nanostructures.
PROCESS TO PREPARE METAL NANOPARTICLES OR METAL OXIDE NANOPARTICLES
The invention is directed to a process to prepare metal nanoparticles or metal oxide nanoparticles by applying a cathodic potential as an alternating current (ac) voltage to a solid starting metal object which solid metal object is in contact with a liquid electrolyte comprising a stabilising cation. The invention is also directed to the use of the nanoparticles as a catalyst.
Catalyst for producing hydrogen and method for producing hydrogen
A metal-supporting catalyst for decomposing ammonia into hydrogen and nitrogen. The catalyst shows a high performance with a low cost and being advantageous from the viewpoint of resources, and an efficient method for producing hydrogen using the catalyst. The catalyst catalytically decomposes ammonia gas to generate hydrogen. The hydrogen generation catalyst includes, as a support, a mayenite type compound having oxygen ions enclosed therein or a mayenite type compound having 10.sup.15 cm.sup.3 or more of conduction electrons or hydrogen anions enclosed therein, and metal grains for decomposing ammonia are supported on the surface of the support. Hydrogen is produced by continuously supplying 0.1-100 vol % of ammonia gas to a catalyst layer that comprises the aforesaid catalyst, and reacting the same at a reaction pressure of 0.01-1.0 MPa, at a reaction temperature of 300-800 C. and at a weight hourly space velocity (WHSV) of 500/mlg.sup.1h.sup.1 or higher.
Method for producing fine catalyst particles and method for producing carbon-supported catalyst
The present invention is to provide fine catalyst particles to which sulfate ions are less likely to be adsorbed, and a carbon-supported catalyst to which sulfate ions are less likely to be adsorbed. Disclosed is a method for producing fine catalyst particles comprising a fine palladium-containing particle and a platinum-containing outermost layer covering at least part of the fine palladium-containing particle, wherein the method comprises: a copper covering step of covering at least part of the fine palladium-containing particle with copper by preparing a second dispersion by mixing a first dispersion comprising fine palladium-containing particles being dispersed in an acid solution with a copper-containing solution, and applying a potential that is nobler than the oxidation reduction potential of copper to the fine palladium-containing particles in the second dispersion, and a platinum covering step of covering at least part of the fine palladium-containing particle with platinum by substituting the copper covering at least part of the fine palladium-containing particle with platinum by mixing the second dispersion and a platinum-containing solution after the copper covering step, with applying a constant potential that is in a range between a potential that is nobler than the oxidation reduction potential of copper and a potential that is less than the oxidation reduction potential of platinum, to the fine palladium-containing particles.
Hydrothermal performance of catalyst supports
A high surface area catalyst with a mesoporous support structure and a thin conformal coating over the surface of the support structure. The high surface area catalyst support is adapted for carrying out a reaction in a reaction environment where the thin conformal coating protects the support structure within the reaction environment. In various embodiments, the support structure is a mesoporous silica catalytic support and the thin conformal coating comprises a layer of metal oxide resistant to the reaction environment which may be a hydrothermal environment.
Methods and compositions for oxygen electrocatalysis
In one aspect, the disclosure relates to catalysts for electrochemical water splitting, in particular catalysts useful for oxygen evolution at an anode in electrochemical water splitting. The disclosed catalysts compositions comprise a catalyst core component, a shell component, and optionally a catalyst outer component; wherein the catalyst core component comprises a composition having the chemical formula M.sub.xP.sub.y; where M is a transition metal; wherein x is a number from about 1 to about 20; wherein y is a number from about 1 to about 20; wherein the shell component comprises a conducting polymer; and wherein the catalyst outer component is a transition metal that is not the same as the transition metal M. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
Synthesis of olefins from oxygen-free direct conversion of methane and catalysts thereof
Provided is a method for the preparation of a metal lattice-doping catalyst in an amorphous molten state, and the process of catalyzing methane to make olefins, aromatics, and hydrogen using the catalyst under oxygen-free, continuous flowing conditions. Such a process has little coke deposition and realizes atom-economic conversion. Under the conditions encountered in a fixed bed reactor (i.e. reaction temperature: 7501200 C.; reaction pressure: atmospheric pressure; the weight hourly space velocity of feed gas: 100030000 ml/g/h; and fixed bed), conversion of methane is 8-50%. The selectivity of olefins is 3090%. And selectivity of aromatics is 1070%. There is no coking. The reaction process has many advantages, including a long catalyst life (>100 hrs), high stability of redox and hydrothermal properties under high temperature, high selectivity towards target products, zero coke deposition, easy separation of products, good reproducibility, safe and reliable operation, etc., all of which are very desirable for industrial application.
BISMUTH-TITANIUM OXIDE NANOWIRE MATERIAL USED FOR PHOTOCATALYSIS, AND PREPARATION METHOD
The present invention relates to bismuth-titanium oxide composite nanowires used for photocatalysis and a preparation method, belonging to the field of inorganic nanomaterials. The preparation of the bismuth-titanium oxide composite nanowires is: polyvinylpyrrolidone (PVP) and bismuth nitrate are added to N-N dimethylformamide (DMF), tetrabutyl titanate and acetylacetone are added after magnetic stirring has been performed for a period of time, continual stirring is performed for more than six hours, and a transparent, stable solution is obtained. Electrospinning is performed on the solution in an electrospinning generation device under certain conditions, and the obtained electrospinning precursor nano fibres are air-fired in a muffle furnace to remove organic matter. After being cooled to room temperature, the electrospinning precursor nano fibres are placed in a tube furnace to be reduced and sintered in a hydrogen atmosphere. The method is energy-saving and environmentally friendly, the conditions are easy to control, costs are low, and large-scale industrial production is easy. The obtained bismuth-titanium oxide nanowires exhibit good degradation activity on methyl orange under illumination, where the methyl orange degradation rate is reaching more than 95% in a reaction lasting for 20 minutes. The obtained bismuth-titanium oxide nanowires have wide application prospects in relation to sewage treatment.