Electrochemical electrodes and methods for the preparation thereof

• US 5,403,462 A
• Filed: 06/24/1993
• Issued: 04/04/1995
• Est. Priority Date: 06/24/1993
• Status: Expired due to Fees

• Current Assignee: Yissum Research Development Company of the Hebrew University of Jerusalem Ltd. (Hebrew University of Jerusalem)
• Original Assignee: Yissum Research Development Company of the Hebrew University of Jerusalem Ltd. (Hebrew University of Jerusalem)
• Inventors: Gun, Genia, Glezer, Victor, Tsionsky, Michael, Lev, Ovadia
• Primary Examiner(s): GORGOS, KATHRYN L
• Application Number:
  US08/080,520
• Time in Patent Office: 649 Days
• Field of Search: 204/403, 204/290 R, 204/416, 204/414, 204/291, 156/308.2, 435/817, 23/295 F
• US Class Current: 204/403.15
• CPC Class Codes: G01N 27/308 at least partially made of carbon
• CPC Class Codes: G01N 27/3277 being a redox reaction, e.g. detection by cyclic voltammetry voltammetry per se G01N27/42, G01N27/48
• CPC Class Codes: Y10S 435/817 Enzyme or microbe electrode
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

An electrochemical electrode, comprising carbon particles distributed in porous, inorganic ceramic material produced by sol-gel technology, wherein the particles form a continuous network which enables conductivity throughout the sol-gel derived matrices.

Claims

1. An electrochemical electrode, comprising carbon particles distributed in an inorganic ceramic, porous, sol-gel derived matrix material, and a dopant selected from the group consisting of a redox couple and a selective compound or functional group immobilized within the sol-gel derived matrix, wherein said carbon particles form a continuous network within said sol-gel derived matrix which enables conductivity throughout said matrix.

2. An electrochemical electrode according to claim 1, wherein a carbon sol-gel composite is deposited on a solid support material selected from the group consisting of organic and inorganic support surfaces.

3. An electrochemical electrode according to claim 1, wherein said inorganic ceramic material is a metal oxide or mixture of oxides.

4. An electrochemical electrode according to claim 1, wherein said inorganic ceramic material is selected from the group consisting of silica, titania, alumina, and a mixture thereof.

5. An electrochemical reference electrode made according to claim 1, wherein said dopant is a redox couple immobilized within said composite sol-gel carbon electrode, forming a reference electrode.

6. An electrochemical selective electrode made according to claim 1, wherein said dopant is a selective compound or functional group immobilized within the composite sol-gel carbon electrode, thus forming a selective electrode.

7. A process for preparing an electrochemical electrode as claimed in claim 1, comprising:

mixing carbon powder with a solution containing precursors of the sol-gel process;

allowing said mixture to gel and dry at temperatures that are lower than temperatures causing pyrolysis; and

incorporating said dopant into said matrix by adding said dopant to said solution containing sol-gel precursors or impregnating said dopant into said matrix, whereby a composite sol-gel carbon electrode, having carbon particles forming a continuous network distributed therein and said dopant immobilized therein is produced.

8. A process according to claim 7, wherein said precursor of the sol gel process are applied to a fixed bed or layer of carbon powder, thus forming a dispersion of the carbon powder in the resulting sol-gel-derived porous glass.

9. An electrochemical electrode, comprising:

(a) a porous, inorganic ceramic xerogel matrix shaped in the configuration of an electrode; and

(b) carbon particles distributed throughout said xerogel matrix to form a continuous network within said matrix, which enables conductivity throughout said matrix; and

(c) a dopant selected from the group consisting of a redox couple and a selective compound or functional group immobilized within the xerogel matrix carbon electrode.

10. An electrochemical reference electrode made according to claim 9, wherein said dopant is a redox couple immobilized within the xerogel carbon electrode, thus forming a reference electrode.

11. An electrochemical selective electrode according to claim 9, wherein said dopant is a selective compound or functional group immobilized within the xerogel carbon electrode, thus forming a selective electrode.