Gas diffusion electrode for carbon dioxide utilization, method for producing same, and electrolytic cell having a gas diffusion electrode

Abstract

A gas diffusion electrode for carbon dioxide utilization, including a metal substrate and an electrically conductive catalyst layer, which is applied to the metal substrate and has hydrophilic pores and/or channels and hydrophobic pores and/or channels, wherein the catalyst layer includes metal particles and a first polymeric binding material; and a porous gas diffusion layer containing the first polymeric binding material is formed on the surface of the catalyst layer. A method produces a gas diffusion electrode for CO2 utilization and an electrolytic cell has a corresponding gas diffusion electrode.

1 . A gas diffusion electrode for the utilization of carbon dioxide, comprising:
 a metallic support, and   an electrically conductive catalyst layer which has been applied to the metallic support and has hydrophilic pores and/or channels and hydrophobic pores and/or channels,   wherein the catalyst layer comprises metallic particles and a first polymeric binder material and a porous gas diffusion layer containing the first polymeric binder material has been formed on the surface of the catalyst layer.   
     
     
         2 . The gas diffusion electrode as claimed in  claim 1 ,
 wherein the gas diffusion layer has a porosity of more than 70%.   
     
     
         3 . The gas diffusion electrode as claimed in  claim 1 ,
 wherein a fluoropolymer is used as first polymeric binder material.   
     
     
         4 . The gas diffusion electrode as claimed  claim 1 ,
 wherein the thickness of the catalyst layer is in the range from 5 nm to 500 nm.   
     
     
         5 . The gas diffusion electrode as claimed in  claim 1 ,
 wherein the first polymeric binder material is embedded partly within the pores and/or channels of the catalyst layer.   
     
     
         6 . The gas diffusion electrode as claimed in  claim 1 ,
 wherein the differential pressure based on the passage of a fluid medium through the gas diffusion layer is in the range from 20 mbar to 220 mbar.   
     
     
         7 . The gas diffusion electrode as claimed in  claim 1 ,
 wherein the hydrostatic pressure based on passage of a fluid medium through the gas diffusion layer is in the range from 20 mbar to 1000 mbar.   
     
     
         8 . The gas diffusion electrode as claimed in  claim 1 ,
 wherein the metallic particles are precoated at least in subregions with a second polymeric binder material.   
     
     
         9 . A process for producing a gas diffusion electrode for utilization of CO 2 , comprising:
 mixing of metallic particles with a first binder material to form a suspension,   applying the suspension to a metallic support, and   introducing the metallic support loaded with the suspension into a precipitation bath to form an electrically conductive catalyst layer,   wherein a porous gas diffusion layer containing the first polymeric binder material is formed on the surface of the catalyst layer within the precipitation bath.   
     
     
         10 . The process as claimed in  claim 9 ,
 wherein a mixture of water and isopropanol is used as precipitation bath.   
     
     
         11 . An electrolysis cell comprising:
 a gas diffusion electrode as claimed in  claim 1 .   
     
     
         12 . The gas diffusion electrode as claimed in  claim 6 ,
 wherein the differential pressure based on the passage of a fluid medium through the gas diffusion layer is in the range from 60 mbar to 200 mbar.   
     
     
         13 . The gas diffusion electrode as claimed in  claim 7 ,
 wherein the hydrostatic pressure based on passage of a fluid medium through the gas diffusion layer is in the range from 200 mbar to 1000 mbar.