CONDUCTIVE TWO-DIMENSIONAL (2D) COVALENT ORGANIC FRAMEWORKS (COFS) AND METHOD OF MAKING AN ELECTRODE MATERIAL
20230197361 · 2023-06-22
Inventors
- Mohamed Eddaoudi (Thuwal, SA)
- Jiangtao JIA (Thuwal, SA)
- Sharath KANDAMBETH (Thuwal, SA)
- Osama Shekhah (Thuwal, SA)
- Husam ALSHAREEF (Thuwal, SA)
Cpc classification
H01G11/02
ELECTRICITY
H01G11/26
ELECTRICITY
Y02E60/13
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H01G11/24
ELECTRICITY
International classification
Abstract
Embodiments include an electrode material including a plurality of cores fused to a plurality of redox active linkers via Aza units to form a layered two-dimensional (2D) Aza-fused pi-conjugated covalent organic framework (COF). Embodiments also include a negative electrode material including the electrode material, as well as a supercapacitor device and an asymmetric supercapacitor device including the electrode material. Embodiments further include a method of making an electrode material including one or more of the following steps: combining a hexaketocyclohexane compound and an aromatic tetraamine compound in a solution; mixing the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound; and heating the mixed solution to form a 2D Aza-fused pi-conjugated COF.
Claims
1. An electrode material comprising: a plurality of cores fused to a plurality of redox active linkers via Aza units to form a layered two-dimensional Aza-fused π-conjugated covalent organic framework (COF).
2. The electrode material according to claim 1, wherein the layered two-dimensional Aza-fused π-conjugated COF has the following chemical structure: ##STR00059## where: ##STR00060## is at least one of an optional bond; and Z is a redox active linker.
3. The electrode material of claim 1, wherein the plurality of cores has at least one of the following chemical structures: ##STR00061## ##STR00062## ##STR00063## where: ##STR00064## is at least one of an optional bond and a point of attachment.
4. The electrode material of claim 1, wherein the plurality of redox active linkers includes at least one aromatic ring, with the proviso that when the redox active linker is a single aromatic ring, the single aromatic ring is not unsubstituted carbocyclic benzene.
5. The electrode material of claim 1, wherein the plurality of redox active linkers includes at least one aromatic ring having at least one of a heteroatom and a substituent, optionally the substituent is selected from the group consisting of halogens, carbonyl groups, carboxylic acid groups, alkoxy groups, a hydroxyl group, amino groups, a nitrile group, a nitro group, optionally substituted linear alkyl groups, optionally substituted branched alkyl groups, a trichloromethyl group, and combinations thereof.
6. The electrode material according to claim 5, wherein the heteroatom is selected from the group consisting of a nitrogen heteroatom, an oxygen heteroatom, a sulfur heteroatom, and combinations thereof.
7. The electrode material of claim 1, wherein the plurality of redox active linkers has the following chemical structure: ##STR00065## wherein: ##STR00066## is at least one of an optional bond and a point of attachment; X.sub.1 and X.sub.2 are independently a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom; R.sup.1 and R.sup.2 are independently a hydrogen, a halogen, carbonyl group, a hydroxyl group, an amino group, an alkoxyl group, an optionally substituted linear alkyl group, an optionally substituted branched alkyl group, or a nitrile group, provided that, when X.sub.1 and X.sub.2 are carbon atoms, at least one of R.sup.1 and R.sup.2 is not a hydrogen, or is a trichloromethyl group, a nitrile group, a nitro group, a carboxylic acid group, or a sulfonyl group; and Q.sub.1 and Q.sub.2 are independently nothing, an optionally substituted aryl group, or an optionally substituted heteroaryl group.
8. The electrode material of claim 1, wherein the plurality of redox active linkers is selected from the group consisting of: ##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## .
9. The electrode material of claim 1, wherein the two dimensional Aza-fused π-conjugated COF has a BET surface area of at least 70 m.sup.2/g.
10. (canceled)
11. A supercapacitor device comprising: an electrode material of claim 1.
12. The supercapacitor device according to claim 11, wherein the supercapacitor device is a symmetric supercapacitor device in which the positive electrode and the negative electrode include the same electrode material.
13. The supercapacitor device according to claim 11, wherein the supercapacitor device is an asymmetric supercapacitor device.
14. The supercapacitor device according to claim 13, wherein the asymmetric supercapacitor device further includes a positive electrode, and a polymer gel electrolyte between the positive electrode and the negative electrode.
15. A method of making an electrode material of claim 1 , the method comprising: combining a hexaketocyclohexane compound and an aromatic tetraamine compound in a solution; mixing the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound; and heating the mixed solution to form a layered two-dimensional Aza-fused π-conjugated COF.
16. The method according to claim 15, wherein the heating step includes heating the mixed solution to a first temperature and subsequently heating the heated solution to a second temperature.
17. The method according to claim 16, wherein the first temperature is less than the second temperature.
18. The method according to claim 16, wherein the first temperature is in a range of about 20° C. to about 99° C.
19. The method according to claim 16 , wherein the second temperature is in a range of about 100° C. to about 150° C.
20. The method of claim 15 , wherein the solution further includes one or more of ethylene glycol, acetic acid, pyridine, mesitylene, and 1,4-dioxane.
21. The method of claim 15 , wherein the aromatic tetraamine compound is selected from the group consisting of 1,2,4,5-tetraamino-benzoquinone; 2,3,6,7-tetraamino-phenazine hydrochloride; 2,3,5,6-tetraaminocyclohexa-2,5-diene-1,4-dione; ##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079## ##STR00080## ##STR00081## ##STR00082## or a salt, a hydrate or a combination thereof.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
Definitions
[0048] As used herein, the term “alkyl” refers to a straight- or branched-chain or cyclic hydrocarbon radical or moiety comprising only carbon and hydrogen atoms, containing no unsaturation, and having 30 or fewer carbon atoms. The term “cycloalkyl” refers to aliphatic cyclic alkyls having 3 to 10 carbon atoms in single or multiple cyclic rings, preferably 5 to 6 carbon atoms in a single cyclic ring. Non-limiting examples of suitable alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, pentyl group, neo-pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, 2-ethylhexyl, cyclohexylmethyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, tridecyl group, tetradcyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, cyclopentyl group, cyclohexyl group, and the like. Additional examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclopentenyl, cyclohexenyl, cyclohexadienyl, cycloheptatrienyl, norbornyl, norpinyl, norcaryl, adamantyl, and spiro[4.5]decanyl groups, as well as their homologs, isomers, and the like. Preferably, the alkyl group is selected from methyl group, ethyl group, butyl group, helptyl group, octadecyl group, and the like. Alkyls can be substituted or unsubstituted. When the term is used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein.
[0049] As used herein, the term “heteroalkyl” refers to an alkyl as defined above having at least one carbon atom replaced by a heteroatom. Non-limiting examples of suitable heteroatoms include nitrogen, oxygen, and sulfur. Examples of cycloheteroalkyl groups include, among others, morpholinyl, thiomorpholinyl, pyranyl, imidazolidinyl, imidazolinyl, oxazolidinyl, pyrazolidinyl, pyrazolinyl, pyrrolidinyl, pyrrolinyl, tetrahydrofuranyl, tetrahydrothiophenyl, piperidinyl, piperazinyl, and the like. Heteroalkyls can be substituted or unsubstituted. When the term is used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein, or a substituent is bonded to a heteroatom, or both.
[0050] As used herein, the term “alkenyl” refers to a straight- or branched-chain hydrocarbon radical or moiety comprising only carbon and hydrogen atoms and having at least one carbon-carbon double bond, which can be internal or terminal. Non-limiting examples of alkenyl groups include: —CH═CH.sub.2 (vinyl), —CH═CHCH.sub.3, —CH═CHCH.sub.2CH.sub.3, —CH.sub.2CH═CH.sub.2 (allyl), —CH.sub.2CH═CHCH.sub.3, —CH═CH—C.sub.6H.sub.5, —CH═CH—, —CH═C(CH.sub.3)CH.sub.2—, and ——CH═CHCH.sub.2—. The groups, —CH═CHF, —CH═CHCl, — CH═CHBr, and the like. Examples of alkenyl groups include ethenyl, propenyl, butenyl, pentenyl, hexenyl, butadienyl, pentadienyl, hexadienyl groups, and the like. Alkenyls can be substituted or unsubstituted. When the term is used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein.
[0051] As used herein, the term “alkynyl” refers to a straight- or branched-chain hydrocarbon radical or moiety comprising only carbon and hydrogen atoms and having at least one carbon-carbon triple bond, which can be internal or terminal. The groups —C≡CH, — C≡CCH.sub.3, and —CH.sub.2C═CCH.sub.3, are non-limiting examples of alkynyl groups. Examples of alkynyl groups include ethynyl, propynyl, butynyl, pentynyl, hexynyl, and the like. Alkynes can be substituted or unsubstituted. When the term is used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein.
[0052] As used herein, the term “aryl” refers to a monocyclic or polycyclic aromatic hydrocarbon radical or moiety comprising only carbon and hydrogen atom, wherein the carbon atoms form an aromatic ring structure. If more than one ring is present, the rings may be fused or not fused, or bridged. The term does not preclude the presence of one or more alkyl groups attached to the first aromatic ring or any additional aromatic ring present. The point of attachment can be through an aromatic carbon atom in the ring structure or a carbon atom of an alkyl group attached to the ring structure. Non-limiting examples of aryl groups include phenyl (Ph), toyl, xylyl, methylphenyl, (dimethyl)phenyl, —C.sub.6H.sub.4—CH.sub.2CH.sub.3 (ethylphenyl), naphthyl, and the monovalent group derived from biphenyl. Further examples of aryl groups having only aromatic carbocyclic ring(s) include phenyl, 1-naphthyl (bicyclic), 2-naphthyl (bicyclic), anthracenyl (tricyclic), phenanthrenyl (tricyclic), pentacenyl (pentacyclic), and like groups. Examples of polycyclic ring systems in which at least one aromatic carbocyclic ring is fused to one or more cycloalkyl and/or cycloheteroalkyl rings include, among others, benzo derivatives of cyclopentane (i.e., an indanyl group, which is a 5,6-bicyclic cycloalkyl/aromatic ring system), cyclohexane (i.e., a tetrahydronaphthyl group, which is a 6,6-bicyclic cycloalkyl/aromatic ring system), imidazoline (i.e., a benzimidazolinyl group, which is a 5,6-bicyclic cycloheteroalkyl/aromatic ring system), and pyran (i.e., a chromenyl group, which is a 6,6-bicyclic cycloheteroalkyl/aromatic ring system). Other examples of aryl groups include benzodioxanyl, benzodioxolyl, chromanyl, indolinyl groups, and the like. When the term is used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein.
[0053] As used herein, the term “heteroaryl” refers to an aryl having at least one aromatic carbon atom in the ring structure replaced by a heteroatom. Non-limiting examples of suitable heteroatoms include nitrogen, oxygen, and sulfur. The term does not preclude the presence of one or more alkyl groups attached to the first aromatic ring or any additional aromatic ring present. The point of attachment can be through an aromatic carbon atom or aromatic heteroatom in the aromatic ring structure or a carbon atom of an alkyl group attached to the aromatic ring structure. Non-limiting examples of heteroaryl groups include furanyl, benzofuranyl, isobenzylfuranyl, imidazolyl, indolyl, isoindolyl, indazolyl, methylpyridyl, oxazolyl, pyridyl, pyrrolyl, pyrimidyl, pyrazinyl, quinolyl, quinazolyl, quinoxalinyl, thienyl, and triazinyl. Additional examples of heteroaryl groups include, for example, the 5- or 6-membered monocyclic and 5-6 bicyclic ring systems shown below:
##STR00001##
##STR00002##
##STR00003##
##STR00004##
##STR00005##
##STR00006##
##STR00007##
##STR00008##
##STR00009##
##STR00010##
##STR00011##
##STR00012##
##STR00013##
##STR00014##
##STR00015##
##STR00016##
##STR00017##
##STR00018##
##STR00019##
##STR00020##
##STR00021##
##STR00022##
##STR00023##
##STR00024##
##STR00025##
##STR00026##
##STR00027##
##STR00028##
##STR00029##
where T is O, S, NH, N-alkyl, N-aryl, N-(arylalkyl) (e.g., N-benzyl), SiH.sub.2, SiH(alkyl), Si(alkyl).sub.2, SiH(arylalkyl), Si(arylalkyl).sub.2, or Si(alkyl)(arylalkyl). Examples of such heteroaryl rings include pyrrolyl, furyl, thienyl, pyridyl, pyrimidyl, pyridazinyl, pyrazinyl, triazolyl, tetrazolyl, pyrazolyl, imidazolyl, isothiazolyl, thiazolyl, thiadiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, indolyl, isoindolyl, benzofuryl, benzothienyl, quinolyl, 2-methylquinolyl, isoquinolyl, quinoxalyl, quinazolyl, benzotriazolyl, benzimidazolyl, benzothiazolyl, benzisothiazolyl, benzisoxazolyl, benzoxadiazolyl, benzoxazolyl, cinnolinyl, IH-indazolyl, 2H-indazolyl, indolizinyl, isobenzofuyl, naphthyridinyl, phthalazinyl, pteridinyl, purinyl, oxazolopyridinyl, thiazolopyridinyl, imidazopyridinyl, furopyridinyl, thienopyridinyl, pyridopyrimidinyl, pyridopyrazinyl, pyridopyridazinyl, thienothiazolyl, thienoxazolyl, thienoimidazolyl groups, and the like. Further examples of heteroaryl groups include 4,5,6,7-tetrahydroindolyl, tetrahydroquinolinyl, benzothienopyridinyl, benzofuropyridinyl groups, and the like. Heteroaryls can be substituted or unsubstituted. When the term is used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein, or a substituent is bonded to a heteroatom, or both.
[0054] As used herein, the term “alkoxy” refers to the group —OR, wherein R is an alkyl, heteroalkyl, aryl, or heteroaryl group. Non-limiting examples of alkoxy groups include: — OCH.sub.3, —OCH.sub.2CH.sub.3, —OCH.sub.2CH.sub.2CH.sub.3, —OCH(CH.sub.3).sub.2, —OCH(CH.sub.2).sub.2, —OC.sub.3H.sub.6, —OC.sub.4H.sub.8, —OC.sub.5H.sub.10, —OC.sub.6H.sub.12, —OCH.sub.2C.sub.3H.sub.6, —OCH.sub.2C.sub.4H.sub.8, —OCH.sub.2C.sub.5H.sub.10, —OCH.sub.2C.sub.6H.sub.12, and the like. The terms “alkenyloxy”, “alkynyloxy”, “aryloxy”, “aralkoxy”, “heteroaryloxy”, and “acyloxy” refer to the group —OR, wherein R is an alkenyl, alkynyl, aryl, aralkyl, heteroaryl, or acyl group, respectively. Examples include without limitation aryloxy groups such as —O—Ph and aralkoxy groups such as —OCH.sub.2—Ph (—OBn) and —OCH.sub.2CH.sub.2—Ph. Alkoxys, alkenyloxys, alkynyloxys, aryloxys, aralkoxys, heteroaryloxys, and acyloxys can each be substituted or unsubstituted. When those terms are used with the “substituted” modifier, one or more hydrogen atoms has been independently replaced by any of the substituents disclosed herein, or a substituent is bonded to a heteroatom, or both.
[0055] As used herein, “amine” and “amino” (and its protonated form) are art-recognized and refer to both unsubstituted and substituted amines, e.g., a moiety that can be represented by the general formula NRR′R″, represented by the structure:
##STR00030##
##STR00031##
[0056] wherein R, R′, and R″ each independently represent a hydrogen, a heteroatom, an alkyl, a heteroalkyl, an alkenyl, —(CH.sub.2).sub.m—Rc or R and R′ taken together with the N atom to which they are attached complete a heterocycle having from 4 to 8 atoms in the ring structure; Rc represents an aryl, a cycloalkyl, a cycloalkenyl, a heterocycle or a polycycle; and m is zero or an integer in the range of 1 to 8, and substituted versions thereof.
[0057] As used herein, the terms “halide,” “halo,” and “halogen” refer to —F, —Cl, — Br, or —I.
[0058] As used herein, the term “substituent” and “substituted” refers to all permissible substituents of the compounds described herein. In the broadest sense, the permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, aromatic and nonaromatic substituents of organic compounds. Examples of substituents include, without limitation, nothing, alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heteroalkyl, substituted heteroalkyl, alkenyl, substituted alkenyl, alkynyl, substituted alkynyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, aralkyl, substituted aralkyl, alkaryl, substituted alkaryl, haloaryl, substituted haloaryl, alkoxy, substituted alkoxy, alkenyloxy, substituted alkenyloxy, alkynyloxy, substituted alkynyloxy, aryloxy, substituted aryloxy, aralkoxy, substituted aralkoxy, heteroaryloxy, substituted heteroaryloxy, acyloxy, substituted acyloxy, acyl, substituted acyl, halo (—F, —Cl, —Br, —I, etc.), hydrogen (—H), carboxyl (—COOH), hydroxy (—OH), oxo (═O), hydroxyamino (— NHOH), nitro (—NO.sub.2), cyano (—CN), isocyanate (—N═C═O), azido (—N.sub.3), phosphate (e.g., —OP(O)(OH).sub.2, —OP(O)(OH)O—, deprotonated forms thereof, etc.), mercapto (—SH), thio (═S), thioether (═S—), sulfonamido (—NHS(O).sub.2—), sulfonyl (—S(O).sub.2—), sulfinyl (— S(O).sub.2—), any combinations thereof, and the like.
[0059] Additional examples of substituents include, but are not limited to, —NC, — S(R.sup.O).sub.2.sup.+, —N(R.sup.O).sub.3.sup.+, —SO.sub.3H, —SO.sub.2R.sup.O, —SO.sub.3R.sup.0, —SO.sub.2NHR.sup.0, —SO.sub.2N(R.sup.0).sub.2, —COR.sup.0, — COOR.sup.0, —CONHR.sup.0, CON(R.sup.0).sub.2, C.sub.1-.sub.40 haloalkyl groups, C.sub.6-14 aryl groups, and 5-14 membered electron-poor heteroaryl groups; where R.sup.0 is a C.sub.1-20 alkyl group, a C.sub.2-20 alkenyl group, a C.sub.2-20 alkynyl group, a C.sub.1-20 haloalkyl group, a C.sub.1-20 alkoxy group, a C.sub.6-14 aryl group, a C.sub.3-14 cycloalkyl group, a 3-14 membered cycloheteroalkyl group, and a 5-14 membered heteroaryl group, each of which can be optionally substituted as described herein. Additional examples of substituents include, but are not limited to, —OR.sup.0, —NH.sub.2, —NHR.sup.0, —N(R.sup.0).sub.2, and 5-14 membered electron-rich heteroaryl groups, where R.sup.0 is a C.sub.1-20 alkyl group, a C.sub.2-20 alkenyl group, a C.sub.2-20 alkynyl group, a C.sub.6-14 aryl group, or a C.sub.3-14 cycloalkyl group.
Discussion
[0060] The present disclosure provides covalent organic framework compositions for use as electrode materials in supercapacitor devices, among other applications. While conventional covalent organic frameworks have very low electronic conductivity and very low specific capacitance (C) values, the electrode materials of the present disclosure provide a covalent organic framework composition having a redox active linker incorporated into a highly porous conductive backbone to obtain a layered two-dimensional Aza-fused π-conjugated covalent organic framework composition with enhanced electrical conductivity, among other properties. The highly porous conductive backbone of the covalent organic framework composition may be useful for electrical double layer capacitor (EDLC)-based charged storage, while the installation of redox active linker into said backbone may be useful for pseudocapacitive charge storage. The extended framework of the two-dimensional aromatized π-conjugated system together with the long-range π-π stacking/orbital overlapping may provide a continuous pathway for electrons which makes them conductive. The present disclosure further provides a new low temperature solvothermal synthetic strategy that permits the incorporation of redox active linkers into the conductive backbone of the covalent organic framework compositions without causing the redox active linkers to decompose. In addition, the present disclosure provides various supercapacitor devices including the electrode materials, among other embodiments.
[0061] Embodiments of the present disclosure provide electrode materials. In some embodiments, the electrode material is or is included in a negative electrode material (e.g., anode). In some embodiments, the electrode material is or is included in a positive electrode material (e.g., cathode). In some embodiments, the electrode materials include a covalent organic framework (COF) composition having the following structural formula:
##STR00032##
where Z is a redox active linker. In some embodiments, the redox active linker, Z, is a redox-functionalized aromatic linker. An unsubstituted carbocyclic benzene, which may be tetravalent, is not redox active and thus is not a redox active linker. For example, in some embodiments, a redox active linker does not include, or is not, an unsubstituted carbocyclic benzene, such as a tetravalent unsubstituted carbocyclic benzene. For example, in some embodiments, the redox active linker, Z, includes at least one aromatic ring, with the proviso that when the redox active linker is a single aromatic ring, the redox active linker is not unsubstituted carbocyclic benzene. In some embodiments, the redox active linker, Z, includes at least one aromatic ring having at least one of a heteroatom and a substituent. For example, in some embodiments, the heteroatom includes at least one of, or is selected from the group consisting of, a nitrogen heteroatom, an oxygen heteroatom, a sulfur heteroatom, and combinations thereof. In some embodiments, the substituent includes at least one of, or is selected from the group consisting of, a hydrogen, a halogen (e.g., at least one of —Cl, —F, — Br, —I, etc.), a carbonyl group (e.g., —C═O), a carboxylic acid group, an alkoxy group (— OR), a hydroxyl group (—OH), an amino group, a nitro group, an optionally substituted linear alkyl group (e.g., a trichloromethyl group), an optionally substituted branched alkyl group, or a nitrile (cyano) group, and combinations thereof.
[0062] In some embodiments, the COF composition, such as for example the COF composition of structural formula I, includes a plurality of cores and a plurality of redox active linkers. For example, in some embodiments, the electrode materials include a plurality of cores fused to a plurality of redox active linkers via Aza units to form a COF composition. In some embodiments, the electrode materials include a plurality of cores fused to a plurality of redox-functionalized aromatic linkers via Aza units to form a COF composition. In some embodiments, the COF composition includes one or more of a layered COF composition, a two-dimensional COF composition, an Aza-fused COF composition, a π-conjugated COF composition, a COF composition based on hexaketocyclohexane (e.g., a Hex-Aza-COF composition), and a COF composition of structural formula I. For example, in some embodiments, the electrode materials include an Aza-fused π-conjugated COF composition. In some embodiments, the electrode materials include a layered two-dimensional Aza-fused π-conjugated COF composition.
[0063] In some embodiments, the plurality of cores is represented by the following structural formula:
##STR00033##
where:
##STR00034##
is at least one of an optional bond and a point of attachment, either or both of which may provide aromaticity.
[0064] In some embodiments, the plurality of cores is represented by at least one of the following structural formulas:
##STR00035##
##STR00036##
##STR00037##
where:
##STR00038##
is at least one of an optional bond and a point of attachment, either or both of which may provide aromaticity.
[0065] In some embodiments, the plurality of redox active linkers is represented by the following structural formula:
##STR00039##
[0071] wherein: [0072] is at least one of an optional bond and a point of attachment, either or both of which may provide aromaticity (e.g., as a point of attachment, a double bond may be formed and/or present (even if not shown), depending on the core, among other things); [0067] X.sub.1 and X.sub.2 are independently a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom; [0068] R.sup.1 and R.sup.2 are independently a hydrogen, a halogen (e.g., at least one of —Cl, — F, —Br, —I, etc.), carbonyl group (e.g., C═O), an alkoxy group (—OR), a hydroxyl group (—OH), an amino group, an optionally substituted linear alkyl group, an optionally substituted branched alkyl group, or a nitrile group, provided that, when X.sub.1 and X.sub.2 are carbon atoms, at least one of R.sup.1 and R.sup.2 is a trichloromethyl group, a nitrile group, a nitro group, a carboxylic acid group, or a sulfonyl group, or is not a hydrogen; and [0069] Q.sub.1 and Q.sub.2 are independently nothing, an optionally substituted aryl group, an optionally substituted heteroaryl group.
[0070] In some embodiments, the plurality of redox active linkers includes at least one of, or is selected from the group consisting of, the following:
##STR00041##
##STR00042##
##STR00043##
##STR00044##
##STR00045##
##STR00046##
##STR00047##
##STR00048##
[0071] In some cases, one or more of the redox active linkers include at least one redox active moieties, such as a nitrile group, a nitro group, a carboxylic acid group, a sulfonyl group or a combination thereof.
[0072] As mentioned above, in some embodiments, the electrode material includes a layered two-dimensional Aza-fused π-conjugated COF composition. In some embodiments, a COF composition is a layered two-dimensional COF where covalent bonds exist or only exist in conjugated two-dimensional sheets or layers, while only weak interactions (e.g., π-π stacking/orbital overlapping) exist between the two-dimensional sheets or layers. In some embodiments, an interlayer repulsion between polarized imine nitrogens of the Aza-fused π-conjugated COF composition prevents ordered stacking and/or long-range ordered stacking of said layers. In some embodiments, the electrode material includes a three-dimensional Aza-fused π-conjugated covalent organic framework. In some embodiments, a COF composition is a three-dimensional COF composition where covalent bonds exist in conjugated two-dimensional sheets or layers and between the two-dimensional sheets or layers.
[0073] In some embodiments, the electrode material has low crystallinity, moderate crystallinity, or high crystallinity, as determined by PXRD. In some embodiments, an interlayer π-π stacking and/or overlapping distance is at least about 1 Å, or at least any one of, equal to any one of, or between any two of about 1, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, 7.0, 7.2, 7.4, 7.6, 7.8, 8.0, 8.2, 8.4, 8.6, 8.8, 9, 9.2, 9.4, 9.6, 9.8, and 10 Å.
[0074] In some embodiments, the electrode material includes a covalent organic framework composition having a unit cell with at least one of AA eclipse packing, inclined packing, ABC staggered packing, and AB staggered packing.
[0075] In some embodiments, the electrode material is provided in the form of a thin film, a layer, a coating, and a nanostructure (e.g., a nanosheet, etc.).
[0076] In some embodiments, the Aza-fused π-conjugated covalent organic framework has a BET surface area of at least 70 m.sup.2/g, or at least any one of, equal to any one of, or between any two of 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, and 145 m.sup.2/g or greater.
[0077] In some embodiments, the electrode material includes a COF composition having at least one of an aggregated layer morphology and an aggregated spherical morphology, as determined by scanning electron microscopy (SEM). In some embodiments, the aggregated layer morphology has particle sizes ranging from about 100 nm to about 100 .Math.ms or greater. In some embodiments, the electrode material includes a COF composition formed by self-assembly of nanosheets as determined by transmission electron microscopy (TEM).
[0078] While not wishing to be bound to a theory, it is believed that the covalent organic framework compositions disclosed herein feature a redox active moiety which is incorporated into the conductive backbone of an Aza-fused π-conjugated covalent organic framework to improve the Aza-fused π-conjugated covalent organic framework’s performance as an electrode material. While supercapacitive energy storage of conventional conjugated microporous polymers, including covalent organic frameworks, is only based on electrical double layer capacitive charge storage, the incorporation of the redox active moiety into the conductive backbone in accordance with the present invention improves the charge storage performance of the covalent organic framework composition by enabling pseudocapacitive charge storage in addition to the electrical double layer capacitive charge storage. In addition, the covalent organic framework compositions not only benefit from the high specific capacitance of pseudocapacitors, but said covalent organic framework compositions also benefit from the long cyclic stability of electrical double layer capacitors (EDLC).
[0079]
[0080] As shown in
##STR00049##
##STR00050##
##STR00051##
##STR00052##
##STR00053##
##STR00054##
##STR00055##
##STR00056##
and the like.
[0081] The solution may include at least one solvent. For example, in some embodiments, the solution may include one or more of ethylene glycol and acetic acid. In some embodiments, the solution includes a 1:1 solvent combination of ethylene glycol and 3.0 M acetic acid (e.g., at 1 mL : 1 mL). In some cases, the solvent is pyridine, mesitylene, 1,4-dioxane, or mixtures thereof.
[0082] The method 100A may further include a mixing step 104A in which the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound are mixed. The manner in which said solution is mixed and/or the technique used for mixing is not particularly limited. In some embodiments, the mixing 104A may include sonicating for a select duration, such as at least 1 min, or at least any one of, equal to any one of, or between any two of 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 45 min, and 60 min or greater. In some embodiments, the mixing 104A includes at least one of agitating, contacting, stirring, swirling, shaking, and the like.
[0083] The method 100A may further include a heating step 106A in which the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound from step 102A and/or 104A (e.g., the sonicated solution) is heated to form an electrode material of the present disclosure. The heating 106A may include heating the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound to a first temperature. The heating 106A may include further heating the solution including the hexaketocyclohexane compound and the aromatic tetraamine compound to a second temperature. In some embodiments, the first temperature is less than the second temperature. In some embodiments, the first temperature is at least about 15° C., or at least any one of, equal to any one of, or between any two of 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 99° C. In some embodiments, the second temperature is at least about 100° C., or at least any one of, equal to any one of, or between any two of, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180 185, 190, 195, and 200° C. or greater. In some embodiments, the first temperature is about 65° C. and the second temperature is between 120° C. and 150° C. The duration of heating at each of the first temperature and the second temperature may be at least about 1 min, or at least any one of, equal to any one of, or between any two of, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, 24 h, 2 d, 3 d, 4 d, 5 d, 6 d, and 7 d or longer.
[0084]
[0085] In some embodiments, the asymmetric supercapacitor device is an all-solid asymmetric supercapacitor device including a gel electrolyte. In some embodiments, the electrolyte is a gel electrolyte including PVA and H.sub.2SO.sub.4. In some embodiments, the electrolyte includes at least one of H.sub.2SO.sub.4 (e.g., 1.0 M H.sub.2SO.sub.4), Na.sub.2SO.sub.4 (e.g., 1.0 M Na.sub.2SO.sub.4), and polyvinyl alcohol (PVA). In some embodiments, the electrolyte includes H.sub.2SO.sub.4/Na.sub.2SO.sub.4. In some embodiments, the electrolyte includes 1.0 M H.sub.2SO.sub.4/1.0 M Na.sub.2SO.sub.4 as electrolyte. In some embodiments, the negative electrode material includes at least one of the electrode material of the present disclosure, a conductive carbon component, a carbon fabric (CF) electrode material, a polymer binder (e.g., PVDF).
[0086] In some embodiments, a redox-functionalized layered two-dimensional Aza-fused π-conjugated covalent organic frameworks (COFs) based on hexaketocyclohexane (Hex-Aza COFs) structures is provided and deployed as anode in asymmetric supercapacitors (ASC). The Hexa-Aza COFs may be synthesized based on a solvothermal condensation reaction of cyclohexanehexone and redox-functionalized aromatic tetramines, such as benzoquinone (Hex-Aza-2) and/or phenazine (Hex-Aza-3). The Hexa-Aza COFs may exhibit a specific-capacitance of 585 Fg.sup.-1 for Hex-Aza-2 and 536 Fg.sup.-1 for Hex-Aza-3 in a three-electrode configuration. Additionally, Hex-Aza COFs may be deployed as an anode material covering a wide voltage-window (e.g., 0 V to -1.0 V). Taking advantage of their anodic characteristics, a two-electrode ASC device may be constructed by combining the Hex-Aza COFs with RuO.sub.2 as cathode. In some embodiments, the complementary potential windows of Hex-Aza-3 and RuO.sub.2 may form an asymmetric device achieving a high voltage-window of 1.7 V. The broad potential-window and high specific-capacitance may form a RuO.sub.2//Hex-Aza-3 two-electrode solid-state ASC device capable of achieving a high energy density value of 39.6 W h kg.sup.-1 with a power density of 1124 W kg.sup.-1.
[0087] In some embodiments, the design and synthesis of layered two-dimensional Aza-fused COFs based on hexaketocyclohexane (Hex-Aza COFs) are provided. Hex-Aza COFs functionalized with redox-active benzoquinone (Hex-Aza-2) or phenazine (Hex-Aza-3) moieties may be synthesized by simple solvothermal condensation reaction. The installation of redox active moieties such as phenazine or benzoquinone in the conductive backbone of Aza-COF framework may be performed to improve the pseudocapacitance, as well as the specific capacitance C values of the Hex-Aza COFs. The synthesized redox functionalized Hex-Aza COFs (Hex-Aza-2 and Hex Aza-3) may exhibit high C values close to 500 Fg.sup.-1 at 1 Ag.sup.-1 (e.g., 585 Fg.sup.-1 for Hex-Aza-2 and 536 Fg.sup.-1 for Hex-Aza-3), which is higher than its unfunctionalized analog Hex-Aza-1 (which was constructed for comparative purposes; see example below). In the three-electrode measurement mode, Hex-Aza COFs may exhibit a majority of the capacitance contribution in the negative potential window (-1.0 V to 0.0 V vs. Hg/Hg.sub.2SO.sub.4), which may enable said COFs to work as anode materials in ASC device. The C values of the redox functionalized Hex-Aza COFs may be comparable to or may exceed the best performing anode materials in ASC, such as MXenes. In order to exploit the high C values and negative electrode characteristics of functionalized Hex-Aza COFs, an ASC solid-state device may be constructed by combing Hex-Aza-3 as the anode and RuO.sub.2 as the cathode. The complementary potential window of the individual electrode material may form a RuO.sub.2//Hex-Aza-3 ASC device that achieves a broad voltage window of 1.7 V. The RuO.sub.2//Hex-Aza-3 ASC solid-state device may deliver a capacitance of 95 F g.sup.-1, at 1 A g.sup.-1 current density. The energy density of RuO.sub.2//Hex-Aza-3 ASC device may also be high (39.6 W h kg.sup.-1) with a power density of 1124 W kg.sup.-1. Excellent cyclic stability may also be achieved with about 89% capacitance retention after 7500 charge-discharge cycles.
[0088] In some embodiments, a series of functionalized (e.g., redox functionalized) Hex-Aza COFs may be deployed as high performing anode materials for ASC devices. The incorporation of redox functionalities such as benzoquinone and phenazine may significantly improve the capacitive performance in Hex-Aza COFs. These newly synthesized redox functionalized Hex-Aza COFs may exhibit a high specific capacitance close to 500 Fg.sup.-1 at 1 Ag.sup.-1 (585 Fg.sup.-1 for Hex-Aza-2 and 536 Fg.sup.-1 for Hex-Aza-3) in three-electrode configuration. To check the effect of the redox-active functionalities on the capacitance contribution, a pristine unfunctionalized COF Hex-Aza-1 may also be constructed for comparison purposes, which exhibits a lower capacitance value of 220 Fg.sup.-1. In some embodiments, a majority of the capacitance contribution of Hex-Aza COFs may be located in the negative potential window. To exploit the high capacitance value and anodic nature of the Hex-Aza COFs, ASC devices may be constructed by coupling them with RuO.sub.2 as cathode. The complementary potential window of the individual electrode may form a RuO.sub.2//Hex-Aza-3 device that achieves a high cell voltage window of 1.7 V. Additionally, the RuO.sub.2// Hex-Aza-3 device may exhibit a specific capacitance of 98 Fg.sup.-1at a current density of 1 Ag.sup.-1, and may deliver an energy density of 39.6 W h Kg.sup.-1 with a power density of 1124 W Kg.sup.-1.
Example 1
Synthesis of Hex-Aza-1 (For Comparative Purposes)
[0089] The synthesis of Hex-Aza covalent organic frameworks (COFs) was performed by solvothermal condensation reaction of hexaketocyclohexane octahydrate (0.06 mmol, 18.7 mg) and 1,2,4,5-benzenetetramine tetrahydrochloride (0.09 mmol, 25.56 mg) in 1:1 solvent combination of ethylene glycol and 3.0 M acetic acid (1 mL:1 mL). Initially, reactants and solvents were transferred to 20 mL screw-capped Pyrex tubes under nitrogen atmosphere, followed by sonication for 15 minutes. After sonication the Pyrex tubes were transferred to a preheated oven at 65° C. The Pyrex tubes were then incubated at 65° C. for 4 hours, and then the temperature of the oven was slowly raised to 150° C. After 4 days of reaction, the Pyrex tubes were removed from the oven. The black Hex-Aza COFs powders were isolated by filtration, washed with solvents acetone and water, and dried under vacuum. All other starting materials, solvents were purchased from a commercial source and used without further purification.
Example 2
Synthesis of Hex-Aza-2
[0090] The synthesis of Hex-Aza COFs was performed by solvothermal condensation reaction of hexaketocyclohexane octahydrate (0.06 mmol, 18.7 mg) and 2,3,5,6-tetraaminocyclohexa-2,5-diene-1,4-dione (
Example 3
Synthesis of Hex-Aza-3
[0091] The synthesis of Hex-Aza COFs was performed by solvothermal condensation reaction of hexaketocyclohexane octahydrate (0.06 mmol, 18.7 mg) and 2,3,6,7-tetraamino-phenazine hydrochloride (
Example 4
Tetraphthalimido-Benzoquinone
[0092] Schlenk flask was charged with 2,3,5,6-tetrachlorocyclohexa-2,5-diene-1,4-dione (10 g, 1 Eq, 40.7 mmol) and potassium 1,3-dioxoisoindolin-2-ide (30 g, 4.00 Eq, 162.7 mmol) and argonated. Anhydrous acetonitrile (100 mL) was added and reaction mixture was placed in preheated to 80° C. oil bath and stirred for 12 h. After cooling to room temperature, the product was filtered, washed with N,N-Dimethylformamide and deionized water at 100° C. for several times. Obtained material was suspended in 100 mL of ethanol, heated to the boiling temperature, and filtered while hot. Obtained material was dried in a vacuum oven at 105° C. for 12 h. Tetraphthalimido-benzoquinone was obtained as yellow solid (23 g, 33 mmol, 82%). .sup.1H NMR (500 MHz, CDCl.sub.3) δ 8.06 (dd, J = 6.7, 3.3 Hz, 8H), 7.69 (dd, J = 6.8, 3.2 Hz, 8H) ppm. .sup.13C NMR (126 MHz, CDCl.sub.3) δ 169.8, 131.69, 127.2, 126.1, 125.3 ppm.
Example 5
Tetraamino-Benzoquinone
[0093] A round bottom flask was charged with tetraphthalimido-benzoquinone (19.00 g, 27.59 mmol) and hydrazine (88 g, 86 mL, 50% Wt, 50 Eq, 1.380 mol). Reaction mixture was kept at 65° C. for 2 h, purple precipitation appear. Reaction was cooled to room temperature and filtrated on suction to collect precipitation. Material was washed with water. Tetramino-benzoquinone (2.00 g, 11.9 mmol, 43%) was obtained as purple solid. .sup.1H NMR (500 MHz, DMSO-d.sub.6) δ 4.54 (s, 4H) ppm. .sup.13C NMR (126 MHz, DMSO-d.sub.6) δ 178.9, 121.4 ppm.
Example 6
PXRD, FTIR, and .SUP.13.C Solid-State NMR of Hex-Aza COFs
[0094] As described above, the synthesis of Hex-Aza COFs was performed by solvothermal condensation reactions. (
[0095] Powder X-Ray Diffraction (XRD) patterns were performed on a D8 Advance X-ray diffractometer (Bruker, Germany) with a Cu Kα radiation (λ=1.5406 Å). In-situ XRD were carried out on a D8 Twin X-ray diffractometer (Bruker, Germany). Scanning electron microscopy (SEM) images and energy-dispersive X-ray spectroscopy (EDS) images were collected on a scanning electron microscope (Merlin, ZEISS, Germany). Transmission electron microscopy (TEM) images and EDS mapping images were taken on a Titan 80-300 CT transmission electron microscope (FEI, Thermo Fisher Scientific, USA). .sup.1H NMR and .sup.13C NMR spectra were recorded on a Bruker Advance III 400 and 500 MHz instruments. Chemical shifts for .sup.1H NMR spectra are reported in ppm (δ, relative to TMS) using DMSO residual peak (δ = 2.50 ppm) in DMSO-d6 as an internal standard and for .sup.1C NMR spectra solvent peaks at 39.52 ppm, and for solutions in CDCl3 solvent peaks at 7.26 and 77.16 ppm, respectively. High resolution dynamic thermogravimetric analysis (TGA) were performed under a continuous N.sub.2 flow and recorded on a TA Instruments hi-res TGA Q500 thermogravimetric analyzer with a heating rate of 5° C. per minute. Fourier-transform Infrared (FT-IR) spectra (4000 – 600 cm.sup.-.sup.1) were recorded on a Thermo Scientific Nicolet 6700 apparatus. Low pressure N.sub.2 adsorption studies of the Hex-Aza COFs were conducted on a fully automated micropore gas analyzer Autosorb-IC (Quantachrome Instruments) at relative pressures up to 1 atm. Hex-Aza COFs sample activation was performed at 65° C. for 10 h.
[0096] The synthesized Hex-Aza COFs, in general, have shown moderate crystallinity as revealed form the PXRD (
[0097] The chemical cross-linking and the formation of an extended framework structure in Hex-Aza COFs were confirmed by FT-IR spectroscopy and .sup.13C solid-state NMR studies. The FT-IR spectroscopy of Hex-Aza-1 and Hex-Aza-3 indicated the formation of new phenazine linkages (C—C═N—C) in the network (1239 and 1241 cm.sup.-1),
Example 7
Thermo-Gravimetric Analysis (TGA) of Hex-Aza COFs
[0098] The thermal stability of the Aza-CMPs was investigated by thermo-gravimetric analysis (TGA). The TGA of Hex-Aza-1 and Hex-Aza-3 did not show any significant weight loss until 400° C. under nitrogen (
Example 8
Preparation of Hex-Aza COF Electrodes
[0099] Hex-Aza COFs were fabricated by drop casting method. About 7 mg of COF powders were sonicated with 2 mg of conductive carbons and 1 mg of PVDF polymer binder in 400 .Math.L of DMF for 1 hour. The suspension was then drop casted on a heated carbon fabric electrode at 150° C. The electrode was then left for drying overnight.
Example 9
Preparation of RuO.SUB.2 Electrode
[0100] RuO.sub.2 electrodes were fabricated by an in situ growth fabrication method. About 120 mg of RuCl.sub.3..sub.XH.sub.2O was mixed with 5 mL of deionized water in a 23 mL Teflon autoclave. A piece of carbon fabric (CF) electrode (1 x 4 cm) was immersed into this solution. The Teflon container was closed afterword and heated to 180° C. for 20 hours. After the completion of the reaction, the CF electrode coated with RuO.sub.2 was washed with deionized water several times and dried at 150° C.
Example 10
Preparation of Gel Electrolyte
[0101] The solid gel electrolyte was prepared by mixing 2 g of polyvinyl alcohol (PVA) polymer in 10 mL 1.0 M H.sub.2SO.sub.4 inside a screw-capped bottle. The mixture was heated at 85° C., under vigorous stirring until the solution mixture became clear. The viscous gel electrolyte was then slowly applied to the electrodes.
Example 11
Fabrication of Asymmetric Devices
[0102] Hex-Aza-3/CF and RuO.sub.2/CF were used as negative and positive electrodes, respectively. The PVA-H.sub.2SO.sub.4 prepared by the above method was applied to the individual electrodes on glass plate and was left over night to achieve a good adherence. After that, both electrodes were sandwiched together.
Example 12
Electrochemical Performance of Hex-Aza COFs
[0103] Electrochemical performance of Hex-Aza COFs was initially evaluated in three-electrode configuration, using 1.0 M H.sub.2SO.sub.4 as the electrolyte and Hg/Hg.sub.2SO.sub.4 and graphite rod as the reference and counter electrodes (
[0104] To determine the percentage of these individual capacitive components in Hex Aza COFs, a scan rate dependent CV analysis was performed. From the current response (i(V)) of Hex-Aza COFs at different scan rates (v) at a fixed potential (V), the capacitive contribution was determined separately according to the following equation.
[0105] where k.sub.1 and k.sub.2 are constants, i(V) is the total current, and v is the scan rate. Here, k.sub.1V and k.sub.2V.sup.½ corresponded to the contributions arising from the surface capacitive effect and diffusion-controlled ion insertion process. The equation can be re-arranged as follows for calculation purposes,
[0106] By plotting i(V)/v.sup.½ against v.sup.½ as y and x axis, a straight line was obtained. The k.sub.1 and k.sub.2 values are calculated from the slope and intercept of the curve. It was found that for the Hex-Aza-2 COF, the majority of the capacitance contribution was pseudo capacitive (72%) (
##STR00057##
[0107] In order to evaluate the charge storage performance of Hex-Aza COFs, the galvanostatic charge/ discharge (GCD) curves were recorded at different current densities (1 A g.sup.-1 to 50 A g.sup.-1) (
[0108] Since Hex-Aza COFs displayed the highest C value in three-electrode configuration (Tables 4-5), the next target was to construct a two-electrode device, which has more practical applications. Since the majority of the capacitance contribution of Hex-Aza COFs was polarized towards the negative potential (-1.0 V to 0.0 V), fabrication of a symmetric device was rather challenging. Attempts to fabricate the symmetric devices of Hex-Aza-2 and Hex-Aza-3 COFs with equal mass loading cathode/anode (m.sub.+/m.sub.-= 1) had not shown promising results (
[0109] The polarized capacitive contribution of Hex-Aza COFs in the negative potential window combined with high specific capacitance values make them an ideal candidate for use as an anode material in ASC. RuO.sub.2 may be used as a cathode material for combining with Hex-Aza COFs, as they exhibit a large potential window in positive region and a high C value with excellent cyclic stability in acidic electrolytes, especially in H.sub.2SO.sub.4. In the literature, RuO.sub.2 has been used as cathode in ASC in combination with other anode materials such as MXene’s, PANi, rGO, anthraquinone, etc. The pseudo-capacitive charge storage in RuO.sub.2 in H.sub.2SO.sub.4 was achieved by the reversible fast proton-coupled-electron exchange process similar to the COF materials. It was expected that the complementary reversible protonation-deprotonation reaction between Hex-Aza COFs and RuO.sub.2 can help build a stable high performing ASC device.
[0110] In three-electrode configuration using 1.0 M H.sub.2SO.sub.4 as the electrolyte, the CV of RuO.sub.2 showed broad redox peaks (around 130 mV at 100 mVs.sup.-1 vs. Hg/Hg.sub.2SO.sub.4) in the selected potential window of -0.4 V to 0.6 V (
##STR00058##
[0111] As a result of the reversible interconversion reaction between R.sub.U2O.sub.3 and RuO.sub.2, protons and electrons were generated at the cathode during the oxidation process of Ru (III) to Ru (IV). The scan rate dependent CV analysis showed the majority of the capacitance of RuO.sub.2 was arising from pseudocapacitive contribution. The GCD curve of RuO.sub.2 showed symmetric triangular charge-discharge curves (
[0112] The electrochemical measurements were performed on a Bio-Logic VMP3 potentiostat in both 3-electrode and 2-electrode configurations using 1.0 M H.sub.2SO.sub.4/1.0 M Na.sub.2SO.sub.4 as electrolyte at room temperature. In 3-electrode measurements Hex Aza COF: carbon: PVDF (7:2:1) served as working electrode, Hg/Hg.sub.2SO.sub.4 was used as reference electrode and a graphite rode was used as the counter electrode, respectively.
[0113] Specific capacitance calculations were made as follows: Gravimetric-specific capacitance C.sub.m(Fg.sup.-1) of electrode materials was calculated from the CV curves by integrating the discharge portion using the following equation:
where, ‘i’ is the current (mA), ‘V’ is the potential window (V), ‘υ’ is the scan rate (mV s.sup.-1), and ‘m’ is the mass of the active material (mg).
[0114] Two-electrode configuration (device measurements):
where, ‘i’ is the current (mA), ‘V’ is the voltage window of the device (V), ‘υ’ is the potential scan rate (mV s.sup.-1), and ‘M’ is the mass of the active electrode materials in both electrodes (mg).
[0115] Gravimetric energy density,
[0116] Gravimetric power density,
[0117] Electrochemical Impedance Spectroscopy: The real (C′) and imaginary (C″) parts of capacitances were calculated using the following equations.
[00125] where |Z| is the absolute value of impedance (Ω), Z′and Z″ are the real and imaginary components of impedance; f is the frequency (Hz).
TABLE-US-00001 Fractional atomic coordinates for the unit cell of Hex-Aza-1 with AA eclipse packing Hex Aza-1 (AA eclipsed) Space group: P6/m, Hexagonal a = b = 16 Å, c = 3.4 Å α =β = 90° , γ = 120° Atom x Y z C1 0.33304 0.58257 0 C2 0.41632 0.66542 0 N1 0.33304 0.49954 0 C3 0.41632 0.49997 0 C4 0.4989 0.58247 0 N2 0.4989 0.6655 0 C5 0.41847 0.41829 0
TABLE-US-00002 Fractional atomic coordinates for the unit cell of Hex-Aza-2 with inclined packing Hex Aza-2 (inclined) Space group: P1 a = b = 16 Å, c = 6.9 Å α =40°, β = 140° , γ = 120° C1 0.2552 0.6605 0 C2 0.2552 0.5775 0 C3 0.3378 0.5776 0 C4 0.4211 0.6604 0 C5 0.4211 0.7435 0 C6 0.3378 0.7437 0 N1 0.5037 0.8266 0 C7 0.5037 0.909 0 C8 0.4211 0.9095 0 N2 0.3378 0.8261 0 N3 0.172 0.6607 0 C9 0.0894 0.5776 0 C10 0.0894 0.4946 0 N4 0.172 0.4947 0 N5 0.3378 0.4946 0 C11 0.4211 0.495 0 C12 0.5037 0.5775 0 N6 0.5037 0.6605 0 C13 0.0061 0.5778 0 C14 0.0061 0.4117 0 C15 0.5869 0.9925 0 C16 0.4211 0.9926 0 O1 0.3371 0.9912 0 O2 0.6695 0.9919 0 C17 0.5869 0.25 0 C18 0.5695 0.2501 0 C19 0.7528 0.333 0 C20 0.7528 0.416 0 C21 0.6695 0.4156 0 C22 0.5869 0.3331 0 N7 0.6695 0.4986 0 C23 0.5869 0.4991 0 C24 0.5044 0.416 0 N8 0.5044 0.333 0 N9 0.5044 0.1675 0 C25 0.5044 0.0845 0 C26 0.5869 0.0846 0 N10 0.6695 0.1671 0 N11 0.8354 0.333 0 C27 0.9187 0.4159 0 C28 0.9187 0.4989 0 N12 0.8354 0.4985 0 C29 0.4211 0.4162 0 O3 0.3378 0.3327 0 C30 0.5869 0.5779 0 O4 0.6695 0.6604 0 O5 0.0061 0.6602 0 O6 0.0061 0.3287 0
TABLE-US-00003 Fractional atomic coordinates for the unit cell of Hex-Aza-3 with ABC staggered packing Hex Aza-3 (ABC staggered) Space group: R3, Trigonal a = b = 24.9 Å, c = 6.6 Å α =β X= 90°, γ = 120° C1 0.33321 0.60996 0.01887 C2 0.39004 0.66678 0.01886 N1 0.33406 0.55572 0.02901 C3 0.38827 0.55502 0.04066 C4 0.44496 0.6117 0.04065 N2 0.44427 0.66592 0.02899 C5 0.66677 0.39003 0.17802 C6 0.60995 0.3332 0.17802 N3 0.66591 0.44426 0.16787 C7 0.61169 0.44495 0.1562 C8 0.55501 0.38826 0.15618 N4 0.55572 0.33405 0.16786 C9 0.50102 0.55569 0.07775 C10 0.44427 0.49895 0.07772 N5 0.44482 0.44481 0.09835 C11 0.49895 0.44426 0.11902 C12 0.55569 0.50101 0.11908 N6 0.55515 0.55515 0.09844 C13 0.50118 0.61187 0.05798 C14 0.38809 0.49879 0.05797 C15 0.49878 0.38808 0.1388 C16 0.61187 0.50117 0.13886
TABLE-US-00004 Comparison of specific capacitance of Hex-Aza-COFs with reported COF based supercapacitors in literature COF material Specific Capacitance (at Current Density/ Scan rate) Electrolyte Voltage Window (Vs. reference electrode) References Hex-Aza-2 585 F g.sup.-1 (1 A g.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -1.0 V to 0.0 V (Vs. Hg—Hg.sub.2SO.sub.4) This Work Hex-Aza-3 536 F g.sup.-1 (1 A g.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -1.1 V to 0.1 V (Vs. Hg—Hg.sub.2SO.sub.4) This Work Hex-Aza-1 220 F g.sup.-1 (1 Ag.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -1.0 V to 0.0 V (Vs. Hg—Hg.sub.2SO.sub.4) This Work [TEMPO]100%-NiP-COF 167 F g.sup.-1(0.1 A g.sup.-1) 0.1 M(C.sub.4H.sub.9).sub.4NClO.sub.4( 3 electrode) 0.0 V to 0.8 V (Vs. AgCl/Ag) Angew. Chem int. Ed.2015,54,6814 DAAQ-TFP-COF 3.0 mF cm.sup.-.sup.2(150 .Math.A cm.sup.-2) 0.1 M TBAPF.sub.6 in MeCN (3 electrode) -2.0 V to -0.5 V (Vs. Ag/AgClO.sub.4) ACS Nano2015,9,3178 DAAQ-TFP-COF 48 ± 10F g.sup.-1 (10 mV 5 s.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -0.3 V to 0.3 V (Vs. Ag/AgCl) J. Am. Chem. Soc.2013, 135, 16821 DAAQ-TFP/PEDOT 350 F cm.sup.-3 (20 mV s.sup.-1) 0.5 M H.sub.2SO.sub.4 (3 electrode) -0.4 V to 0.6 V (Vs. Ag/AgCl) ACS Cent. Sci.2616,2, 667 TpPa-(OH).sub.2-COF 344 F g.sup.-1 (1 A g.sup.-1) 1.0 M Phosphate buffer (pH=7.2) (3 electrode) -0.2 V to 0.5 V (Vs. SCE) Chem. Mater.2017,29, 2074 TpOMe-DAQ 135 F g.sup.-1 (0.35 A g.sup.-1) 2.0 M H.sub.2SO.sub.4 (3 electrode) -0.5 V to 0.5 V (Vs. Hg—Hg.sub.2SO.sub.4) J. Am. Chem. Soc.2018, 140,10941 Dq.sub.1Da.sub.1TpCOF 111 F g.sup.-1 (1.56 mA cm.sup.-2) 1.0 M H.sub.2SO.sub.4 (3 electrode) -0.5 V to 0.3 V (Vs. Ag/AgCl) ACS Appl. Mater. Interfaces2018, 10, 28139
TABLE-US-00005 Comparison of specific capacitance of Hex-Aza COFs with various anode (-Ve electrode) materials reported in literature Name Specific Capacitanc e (at Current Density/ Scan rate) Electrolyte Voltage Window (Vs. reference electrode) References Hex-Aza-2 585 F g.sup.-1 (1 A g.sup.-1 1.0 M H.sub.2SO.sub.4 (3 electrode) -1.0 V to 0.0 V (Vs. Hg—Hg.sub.2SO.sub.4) This Work Hex-Aza-3 536 F g.sup.-1 (1 A g.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -1.1 V to 0.1 V (Vs. Hg—Hg.sub.2SO.sub.4) This Work Hex-Aza-1 220 F g.sup.-1 (1 A g.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -1.0 V to 0.0 V (Vs. Hg—Hg.sub.2SO.sub.4) This Work Ppy-65 wt% carbon 433 F g.sup.-1 (1 mV s.sup.-1) 6.0 M KOH(3 electrode) -1.0 V to 0.0 V (Vs. Hg—HgO) J. Power Sources, 2010,195,6964 H-TiO.sub.2@C 253.4 F g.sup.-1 (10 mv s.sup.-1) 5.0 M LiCl(3 electrode) -1.0 V to 0.0 V (Vs. Ag/AgCl) Adv. Mater.2013, 25,267 Fe.sub.2O.sub.3 Nano rodes 64.5 F g.sup.-1 (1 A g.sup.-1) 1.0 M KOH(3 electrode) -0.8 V to 0.0 V (Vs. SCE) Adv. Mater.2014,26, 3148 RGO/cMWCNT films 193 F g.sup.-1 (1 A g.sup.-1) 1.0 M potassium polyacrylate (PAAK)/KCl (3 electrode) -0.9 V to -0.1 V (Vs. SCE) J. Mater. Chem. A 2014,2,1458 PEDOT@Au@PEN 175 F g.sup.-1 (1 mA cm.sup.2) 1.0 M H.sub.2SO.sub.4 (3 electrode) -0.5 V to 0.3 V (Vs. Ag/AgCl) J. Mater. Chem. A 2015,3,7368 PANi-20 wt% MWNTs 670 F g.sup.-1 (2 mV s.sup.-1) 1.0 M H.sub.2SO.sub.4 (3 electrode) -0.8 V to 0.4 V (Vs. Hg—Hg.sub.2SO.sub.4) Electrochim. Acta, 2005, 50,2499