Co-electrolysis cell design for efficient co2 reduction from gas phase at low temperature

Patent metadata

Field	Value
Publication number	US-2020308718-A1
Application number	US-201816633617-A
Country	US
Kind code	A1
Filing date	May 24, 2018
Priority date	Jul 24, 2017
Publication date	Oct 1, 2020
Grant date	—

Abstract

A membrane electrode assembly for an electrochemical cell, in particular a co-electrolysis cell for CO2 reduction reaction, can overcome the problem of parasitic CO2 pumping from cathode to anode side and, at the same time, maintain good Faradaic efficiency towards CO2 reduction reaction in a co-electrolysis system where pure or diluted gaseous CO2 is used. The assembly includes an MEA, having an anode, a cathode, a polymer ion exchange membrane between cathode and anode, an additional ion exchange polymer film between the cathode and the polymer ion exchange membrane and a discontinuous interface formed between the additional polymer film located at the cathode side and the ion exchange membrane.

First claim

1 - 9 . (canceled)

10 . An electrochemical co-electrolysis cell for the reduction of carbon dioxide, the cell comprising a membrane electrode assembly (MEA) including:
a) an anode electrode layer, a cathode electrode layer, and a cation exchange polymer membrane disposed between said anode electrode layer and said cathode electrode layer; b) said cathode electrode layer including a mixture of a cathode catalyst material and an anion exchange ionomer, and a distribution of said anion exchange ionomer within said cathode electrode layer causing said anion exchange ionomer to:
(i) form a discontinuous contact interface with said cation exchange polymer membrane, and
(ii) separate said cathode catalyst material from said cation exchange polymer membrane.

11 . A membrane electrode assembly (MEA), comprising:
an anode electrode layer; a cathode electrode layer; and an ionic conductive polymer membrane disposed between said anode electrode layer and said cathode electrode layer; said ionic conductive polymer membrane being formed of two layers of different ionic conductive polymers forming a discontinuous polymeric interface between said two layers of different ionic conductive polymers.

12 . The membrane electrode assembly according to claim 11 , wherein:
a) one of said two layers of different ionic conductive polymers is an anionic conductive polymer being in contact with a cathode catalyst layer included in said cathode electrode layer; and b) the other of said two layers of different ionic conductive polymers is a cationic conductive layer being in contact with said anode electrode layer.

13 . The membrane electrode assembly according to claim 12 , wherein said cathode electrode layer has a side in contact with said anionic polymer membrane and has a 3D porous structure including a catalytic active powder and an anionic conductive polymer.

14 . The membrane electrode assembly according to claim 12 , wherein:
said anionic conductive layer is deposited on said cathode catalyst layer; and said anionic conductive layer has a thickness equal to approximately 10% of a thickness of said cationic polymer layer and takes a porosity of said cathode catalyst layer.

15 . An electrochemical device capable of transforming CO 2 into fuels or other chemical molecules including CO, HCOO—, CH 4 , C 2 H 4 and alcohols using electricity, water and CO 2 gas, the device comprising an MEA according to claim 10 .

16 . An electrolyzer for hydrogen production, the electrolyzer comprising an MEA according to claim 10 .

17 . A fuel cell, comprising an MEA according to claim 10 .

18 . A process for fabricating a membrane electrode assembly (MEA), the process comprising the following steps:
i) fabricating a cathode gas diffusion electrode by coating a mixture of cathode catalyst material and anion exchange ionomer onto one side of a gas diffusion layer; ii) applying an additional coating of anion exchange ionomer onto the cathode gas diffusion electrode; iii) bringing the anion exchange ionomer-coated side of the cathode gas diffusion electrode in contact with one side of a cation exchange polymer membrane; and iv) bringing an opposite side of the cation exchange polymer membrane in contact with an anode electrode layer.

Assignees

• Scherrer Inst Paul

Inventors

• Patru Alexandra
• Schmidt Thomas Justus
• Binninger Tobias
• Pribyl Bernhard

Classifications

• Y02E60/50

  Fuel cells · CPC title

• C25B11/052

  Electrodes comprising one or more electrocatalytic coatings on a substrate · CPC title

• C25B11/032

  Gas diffusion electrodes · CPC title

• C25B9/21

  two or more diaphragms · CPC title

• C25B3/26

  of carbon dioxide · CPC title