Patent US4367131A successfully refreshed from Google Patents.
US4367131A
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Photolytic production of hydrogen from water
Assignee: RESEARCH Corp A NOT FOR PROFIT CORP OF NEW YORK
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Filing: 1981-07-02
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Granted: 1983-01-04
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Expires: 2001-07-02
Abstract
Abstract The photodissociation of water into hydrogen gas is mediated by a catalytic dispersion of fine metal particles. This dispersion is stabilized by polymers of alkylene glycols which are adsorptive to said particles and which act as protective agents in solution.
Inventors
- 👤 Michael Gratzel
- 👤 Pierre-Alain Brugger
- 👤 Pierre Cuendet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:06
CPC Classifications
B; B01; B01J; B01J35/00; B01J35/30; B01J35/39; B01J23/00; B01J23/38; B01J23/40; B01J23/42; B01J31/00; B01J31/02; B01J31/06; B01J31/068; B01J35/20; B01J35/23; B01J35/40; B01J35/45; C; C01; C01B; C01B3/00; C01B3/02; C01B3/04; C01B3/042; C01B3/046; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/36; Y10; Y10S; Y10S204/00; Y10S204/902; Y10S204/903; Y10S204/904
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
96 words
A catalyst capable of forming a stable dispersion in an aqueous medium for mediating the evolution of hydrogen from water by photolysis, said catalyst comprising an intimate admixture of one or more Noble metals in finely divided form and a water permeable protective agent adsorptive to said metal consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --0--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 2
Dependent Claim
96 words
A catalyst capable of forming a stable dispersion in an aqueous medium for mediating the evolution of hydrogen from water by photolysis, said catalyst comprising an intimate admixture of one or more Noble metals in finely divided form and a water permeable protective agent adsorptive to said metal consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --0--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 3
Dependent Claim
17 words
The catalyst of claim 1 wherein the catalyst particle size is no greater than 50 A diameter.
Claim 4
Dependent Claim
49 words
A catalyst according to claim 1 for mediating the photolytic evolution of hydrogen from water wherein said Noble metal is selected from the group consisting of platinum, palladium, rhodium, ruthenium, iridium, osmium, silver or gold admixed with a protective agent having a molecular weight of from between about 200-200,000.
Claim 5
Dependent Claim
18 words
The catalyst of claim 3 wherein the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 6
Dependent Claim
12 words
The catalyst of claim 3 wherein the protective agent is Carbowax 20-M.
Claim 7
Dependent Claim
12 words
The catalyst of claim 3 wherein the metal is platinum or palladium.
Claim 8
Dependent Claim
23 words
The catalyst of claim 3 wherein the metal is platinum and the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 9
Dependent Claim
17 words
The catalyst of claim 3 wherein the metal is platinum and the protective agent is Carbowax 20-M.
Claim 10
Independent Claim
113 words
A method for preparing a stabilized metal catalyst for mediating the photolytic production of hydrogen from water which comprises: (1) adding a reducible Noble metal compound or mixture of Noble metal compounds to an aqueous medium; (2) reducing said Noble metal compound or mixture of Noble metal compounds; and (3) adding to the resulting mixture of step (2) a protective agent selected from the group consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --O--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 11
Independent Claim
113 words
A method for preparing a stabilized metal catalyst for mediating the photolytic production of hydrogen from water which comprises: (1) adding a reducible Noble metal compound or mixture of Noble metal compounds to an aqueous medium; (2) reducing said Noble metal compound or mixture of Noble metal compounds; and (3) adding to the resulting mixture of step (2) a protective agent selected from the group consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --O--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 12
Dependent Claim
24 words
The method of claim 9 wherein the mixture of step (2) is adjusted to a pH in the range of from between about 6-8.
Claim 13
Dependent Claim
38 words
The method of claim 9 wherein the Noble metal is selected from the group consisting of platinum, palladium, rhodium, ruthenium, iridium, osminum, silver or gold and the protective agent has a molecular weight of from between about 200-200,000.
Claim 14
Dependent Claim
16 words
The method of claim 9 wherein the catalyst particle size is no greater than 50 A.
Claim 15
Dependent Claim
18 words
The method of claim 9 wherein the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 16
Dependent Claim
12 words
The method of claim 13 wherein the protective agent is Carbowax 20-M.
Claim 17
Dependent Claim
26 words
The method of claim 9 wherein the Noble metal is platinum or palladium and the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 18
Dependent Claim
18 words
The method of claim 9 wherein the Noble metal is platinum and the protective agent is Carbowax 20-M.
Claim 19
Dependent Claim
108 words
In the photolytic method for producing hydrogen from water by treatment with a reducing species capable of donating electrons to water; the improvement which comprises: conducting the reduction step in the presence of a stabilized and finely dispersed catalyst comprising one or more Noble metals in finely divided form in intimate admixture with a protective agent selected from the group consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --O--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 20
Dependent Claim
108 words
In the photolytic method for producing hydrogen from water by treatment with a reducing species capable of donating electrons to water; the improvement which comprises: conducting the reduction step in the presence of a stabilized and finely dispersed catalyst comprising one or more Noble metals in finely divided form in intimate admixture with a protective agent selected from the group consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --O--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 21
Dependent Claim
38 words
The method of claim 17 wherein the Noble metal is selected from the group consisting of platinum, palladium, rhodium, ruthenium, iridium, osmium, silver or gold and the protective agent has a molecular weight of from between about 200-200,000.
Claim 22
Dependent Claim
18 words
The method of claim 17 wherein the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 23
Dependent Claim
12 words
The method of claim 19 wherein the protective agent is Carbowax 20-M.
Claim 24
Dependent Claim
26 words
The method of claim 17 wherein the Noble metal is platinum or palladium and the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 25
Dependent Claim
18 words
The method of claim 21 wherein the Noble metal is platinum and the protective agent is Carbowax 20-M.
Claim 26
Dependent Claim
16 words
The method of claim 17 wherein the catalyst particle size is no greater than 50 A.
Claim 27
Independent Claim
149 words
A method for the photolytic production of hydrogen from water which comprises: subjecting an aqueous solution containing photosensitizer to irradiation with light from the visible region of the spectrum to afford an excited state of the photosensitizer molecule; and contacting said excited state photosensitizer with an electron acceptor to afford a reduced acceptor species which, in aqueous solution in the presence of an electron donor and a stabilized and finely dispersed catalyst reduces water to form hydrogen gas; said catalyst comprising one or more Noble metals in finely divided form in intimate admixture with a protective agent selected from the group consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --O--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 28
Independent Claim
149 words
A method for the photolytic production of hydrogen from water which comprises: subjecting an aqueous solution containing photosensitizer to irradiation with light from the visible region of the spectrum to afford an excited state of the photosensitizer molecule; and contacting said excited state photosensitizer with an electron acceptor to afford a reduced acceptor species which, in aqueous solution in the presence of an electron donor and a stabilized and finely dispersed catalyst reduces water to form hydrogen gas; said catalyst comprising one or more Noble metals in finely divided form in intimate admixture with a protective agent selected from the group consisting of one or more alkylene glycol polymers derived from monomer units of the formula: --O--(CH.sub.2).sub.n --O-- wherein n is an integer greater than 1 and in which at least a portion of said polymer is comprised of monomer units having n equal to or greater than 3.
Claim 29
Dependent Claim
38 words
The method of claim 24 wherein the Noble metal is selected from the group consisting of platinum, palladium, rhodium, ruthenium, iridium, osmium, silver or gold and the protective agent has a molecular weight of from between about 200-200,000.
Claim 30
Dependent Claim
18 words
The method of claim 24 wherein the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 31
Dependent Claim
12 words
The method of claim 26 wherein the protective agent is Carbowax 20-M.
Claim 32
Dependent Claim
26 words
The method of claim 24 wherein the Noble metal is platinum or palladium and the protective agent is a copolymer of ethylene glycol and propylene glycol.
Claim 33
Dependent Claim
21 words
The method of claim 28 wherein the Noble metal is platinum in colloidal form and the protective agent is Carbowax 20-M.
Claim 34
Dependent Claim
16 words
The method of claim 24 wherein the catalyst particle size is no greater than 50 A.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-03 | 1986-07-05 | 1987-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-03 | 1990-07-05 | 1991-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-03 | 1994-07-05 | 1995-01-04 | $7700.00 | Window Closed / Lapsed |