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US4132619A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrocatalyst

Assignee: Scientific Research Foundation
•
Filing: 1977-08-02
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Granted: 1979-01-02
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Expires: 1997-08-02
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Abstract

Abstract The invention relates to mixed oxides of the spinel type or of similar structure, containing a quantity of boron adapted to reduce the electrical resistance of the oxide by a factor of at least 1000 calculated on the corresponding compound without boron, some of the preferred compounds being selected from compounds of the formulae CoxFe3-xOn and CoxNi3-xOn, wherein x is between 0.05 and 3, n is between 3 and 5, containing from 0.05 to 20 atom per cent boron calculated on the mixed oxides, wherein part of the Co,Ni. or Fe may be substituted by an equivalent quantity of magnesium or calcium, said compounds being optionally doped with lithium; electrocatalytically active electrodes made from such compounds and electrical cells containing such electrodes.

Inventors

  • 👤 Yitzchak Klein
  • 👤 Jonathan R. Goldstein

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 13:04
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/70; B01J23/76; B01J23/78; B01J23/005; B01J23/74; C; C25; C25B; C25B1/00; C25B1/01; C25B1/02; C25B11/00; C25B11/04; C25B11/051; C25B11/073; C25B11/091; H; H01; H01M; H01M10/00; H01M10/42; H01M10/52; H01M4/00; H01M4/86; H01M4/90; H01M4/9016; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y02E60/30; Y02E60/50

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 50 words
Crystalline mixed oxide selected from compounds of the formulae Co x Fe 3-x O n and Co x Ni 3-x O n , wherein x is between 0.05 and 3, n is between 3 and 5, containing from about 0.05 to 20 atom percent boron calculated on the mixed oxide.
Claim 2
Dependent Claim 50 words
Crystalline mixed oxide selected from compounds of the formulae Co x Fe 3-x O n and Co x Ni 3-x O n , wherein x is between 0.05 and 3, n is between 3 and 5, containing from about 0.05 to 20 atom percent boron calculated on the mixed oxide.
Claim 3
Dependent Claim 13 words
A crystalline mixed oxide according to claim 1, of the spinel crystal type.
Claim 4
Dependent Claim 15 words
A crystalline mixed oxide according to claim 1 wherein n is between 3.6 and 4.
Claim 5
Dependent Claim 28 words
A crystalline mixed oxide compound according to claim 1 wherein part of the cobalt, nickel or iron is replaced by an equivalent quantity of magnesium or calcium lithium.
Claim 6
Dependent Claim 41 words
Crystalline oxides containing boron, according to claim 1 consisting of oxides of the transition metals Co, Ni, Fe, optionally containing magnesium or calcium in a proportion so as to replace some of the Co, Ni or Fe, of spinel crystal structure.
Claim 7
Dependent Claim 10 words
Borided mixed oxides according to claim 1 in powder form.
Claim 8
Dependent Claim 15 words
Borided mixed oxides according to claim 1 in the form of an active surface layer.
Claim 9
Dependent Claim 21 words
A mixed oxide containing boron, according to claim 1 wherein part of the cobalt, nickel or iron is replaced by lithium.
Claim 10
Dependent Claim 29 words
A mixed oxide according to claim 6 in the form of a powder having a surface area of at least 20 m 2 /g determined by the BET techique.
Claim 11
Dependent Claim 14 words
An electrocatalytically effective surface comprising as active substance a mixed according to claim 1.
Claim 12
Dependent Claim 15 words
An electrocatalytically active electrode comprising as electrocatalytically active substance a spinel according to claim 3.
Claim 13
Dependent Claim 30 words
A process for producing an electrocatalytically active mixed oxide containing boron according to claim 1 which comprises reacting the mixed oxide in powder form with sodium borohydride at elevated temperature.
Claim 14
Dependent Claim 28 words
A process according to claim 12 for producing an electrocatalytically active borided mixed oxide which comprises reacting the mixed oxides with boric acid and carbon at elevated temperature.
Claim 15
Dependent Claim 46 words
A process for producing lithiated electrocatalytically active borided mixed oxides according to claim 4, of increased corrosion resistance in alkaline solutions, which comprises applying to said spinel a suitable lithium salt and subjecting same to a heat treatment, thus incorporating therein a predetermined quantity of lithium.
Claim 16
Dependent Claim 37 words
A process according to claim 14, wherein the mixed oxide is coated with a solution of lithium nitrate, iron nitrate and cobalt nitrate and the heat treatment is at a temperature of from 400° to 800° C.
Claim 17
Dependent Claim 28 words
Electrical secondary cells, fuel cells or electrolysis cells comprising an electrocatalytically active borided mixed oxide claimed in claim 1 in the form of an electrode or auxiliary electrode.
Claim 18
Dependent Claim 12 words
Electrochemical cells according to claim 16, wherein the borided spinel is lithiated.

References Cited (Backward Citations)

US2691660A Cited
US3649485A Cited
US3711382A Cited
US3781350A Cited
US3986892A Cited
US3926844A Cited
US4061549A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-01-01 1982-07-03 1983-01-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-01-01 1986-07-03 1987-01-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-01-01 1990-07-03 1991-01-02 $7700.00 Window Closed / Lapsed

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