ELECTROLYTIC CELL EQUIPPED WITH MICROELECTRODES

• US 20150308003A1
• Filed: 11/08/2013
• Published: 10/29/2015
• Est. Priority Date: 11/09/2012
• Status: Active Grant

• Current Assignee: Industrie De Nora S.p.A
• Original Assignee: Industrie De Nora S.p.A
• Inventors: GULLA, Andrea Francesco
• Granted Patent: US 11,421,332 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C23C 14/18 on other inorganic substrates
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/278 doping or introduction of a secondary phase in the diamond
• CPC Class Codes: C23C 16/511 using microwave discharges
• CPC Class Codes: C25B 1/13 Ozone
• CPC Class Codes: C25B 1/26 Chlorine; Compounds thereof by simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine C25B1/34
• CPC Class Codes: C25B 1/30 Peroxides
• CPC Class Codes: C25B 11/02 characterised by shape or form
• CPC Class Codes: C25B 11/051 Electrodes formed of electrocatalysts on a substrate or carrier

Abstract

The invention relates to an electrolytic cell equipped with microelectrodes for the generation of un-separated products and the method for obtaining it. The cell and the microelectrodes of the present invention are obtained using a technology for the production of microelectromechanical systems (MEMS). The anodic and cathodic microelectrodes have an electrocatalytic coating and are mutually intercalated at an interelectrodic gap lower than 300 micrometres.

Claims

1. Electrolytic cell for generation of unseparated anodic and cathodic products consisting of a lithographically-patternable substrate having a surface, a multiplicity of anodic and cathodic microelectrodes formed on said surface, said anodic and cathodic microelectrodes being mutually intercalated at an interelectrodic gap lower than 100 micrometres and having an average surface roughness Ra lower than 0.05 μ

m.

2. Electrolytic cell according to claim 1 wherein said average surface roughness Ra is lower than 0.01 μ

m.

3. Electrolytic cell according to claim 1 wherein at least said anodic microelectrodes comprise an external layer consisting of a vacuum-deposited boron-doped diamond film.

4. Electrolytic cell according to claim 1, wherein said microelectrodes comprise an external layer made of a material containing at least one element selected from the group consisting of Pt, Pd, Ir, Ru, Rh, Nb and Ti.

5. Electrolytic cell according to claim 1 wherein said lithographically-patternable substrate is made of a semiconductor material.

6. Electrolytic cell according to claim 4 comprising an intermediate layer of a metallic material selected from the group consisting of Co, Cr, Mo, W, Ni, Ti and alloys thereof interposed between said external layer and said lithographically-patternable substrate.

7. Electrolytic cell according to claim 3, wherein said external layer consists of a boron-doped diamond film containing at least 5000 ppm of boron doping.

12. Process of manufacturing of mixed oxidant solutions of variable composition comprising applying a program of direct electrical current at variable current density by means of a microprocessor integrated to a cell according to claim 1.

13. Process according to claim 12 wherein said mixed oxidant solutions contain at least one species selected between ozone, oxygen radicals, nascent oxygen, peroxides, hypochlorite ion and nascent chlorine.

14. Process according to claim 12 wherein said cell is supplied with an aqueous electrolyte polluted with organic substances.

15. Device for dispensing sterilising, disinfecting or detergent substances equipped with at least one cell according to claim 1.

8. Method of manufacturing of an electrolytic cell comprising the following steps:

providing a substrate with fingers according to a predefined pattern by a lithographic technique;

applying an external electrode layer by vapour phase physical or chemical deposition technique upon said fingers to obtain anodic and cathodic microelectrodes being mutually intercalated at an interelectrodic gap lower than 100 micrometres and having an average surface roughness Ra lower than 0.05 μ

m.

9. Method according to claim 8 wherein said external electrode layer comprises a material containing at least one element selected from the group consisting of Pt, Pd, Ir, Ru, Rh, Nb and Ti, optionally comprising an intermediate layer of a metal selected from the group consisting of Co, Cr, Mo, W, Ni, Ti and alloys applied by vapour phase physical or chemical deposition technique.

10. Method according to claim 8 wherein said substrate is topped with a SiO₂ layer and said external electrode layer is obtained by coating said substrate with a boron-doped diamond film by microwave-assisted chemical vapour deposition.

11. Method according to claim 8 wherein said lithographic technique is MEMS photolithography, MEMS laser etching or a combination of the two.