Copper and antimony based material and electrode for the selective conversion of carbon dioxide to carbon monoxide

Abstract

An electrocatalyst material comprising cuprous oxide and antimony, the process for the production thereof and its use in the electrochemical reduction of CO2 to CO with high selectivity and efficiency are described.

1 . An electrocatalyst material consisting of copper(I) oxide (Cu 2 O) containing antimony, wherein the amount of antimony is between 5% to 30% by weight. 
     
     
         2 . The electrocatalyst material according to  claim 1 , wherein the amount of antimony is between 5.2% and 26.4% by weight. 
     
     
         3 . The electrocatalyst material according to  claim 2 , wherein the amount of antimony is between 17.2% and 23.9% by weight. 
     
     
         4 . An electrode comprising powder of an electrocatalyst material of  claim 1  and a conductive material deposited on a support, in a weight ratio between electrocatalyst material and conductive material between 9:1 and 19:1. 
     
     
         5 . The electrode according to  claim 4 , wherein the conductive material is in the form of powder. 
     
     
         6 . The electrode according to  claim 4 , wherein the conductive material is carbon based. 
     
     
         7 . The electrode according to  claim 6 , wherein the conductive material is chosen from carbon black, graphite, graphene, carbon nanotubes and mixtures thereof. 
     
     
         8 . The electrode according to  claim 4 , wherein the support is selected from conductive carbon paper, conductive carbon cloth and metal mesh. 
     
     
         9 . The electrode according to  claim 4 , wherein the powder of the electrocatalyst material and possibly of the conductive material are stabilized on the support with an ionomer. 
     
     
         10 . A process for the production of the electrocatalyst material of  claim 1 , comprising the following steps:
 a) dissolving a copper(II) salt and an antimony(III) salt in a solvent selected from ethanol, ethylene glycol, acetylacetone, diethylamine, ethylenediamine, oleylamine, N,N-dimethylformamide, mixtures of these solvents with each other, with water or with aqueous solutions of D-glucose, hydrazine hydrate, amino acids or sodium carboxymethylcellulose, obtaining a solution;   b) heating the solution in a microwave oven at a temperature between 180 and 230° C. for a time between 1 and 10 minutes;   c) separating the precipitate from the solution and its drying.   
     
     
         11 . The process according to  claim 10 , wherein the copper(II) salt is selected from acetate, sulfate and nitrate, and the antimony(III) salt is selected from acetate, sulfate and nitrate. 
     
     
         12 . A method for the selective electrochemical reduction of CO 2  to CO, comprising the use of an electrode of  claim 4  at a potential between -0.69 V to -1.09 V.