Metal catalysts in tandem with carbon-based catalysts for CO2 conversion to carbon-based molecules

Stanford researchers have developed a novel electrode composed of copper-based catalyst and a carbon-based catalyst to directly convert CO₂ into ethylene, a valuable carbon-based molecule. Ethylene (C₂H₄) is particularly attractive due to its major importance as a feedstock chemical for various applications.

The electrocatalyst is composed of copper-based material and a carbon-based catalyst which enables the formation of CO from CO₂. The two materials are integrated into gas diffusion electrodes for direct conversion of vapor-fed CO₂ into ethylene. The carbon-based catalyst converts CO₂ to CO, and the copper surface converts CO to ethylene. The tandem electrocatalyst enables the high selectivity and formation rate of ethylene on a practical scale, achieving 40% faradaic efficiency (FE) at 150 mA cm^-2 and 3.2 V in a membrane electrode assembly electrolyzer. The catalytic performance of the tandem catalysts shows higher energy conversion and lower working voltages compared to any catalyst previously reported. Moreover, this strategy applied towards other catalyst-electrode geometries could be broadly applicable towards reactions for accessing other valuable carbon-based molecules from CO₂ like ethanol, acetate, etc.

Figure:

Stage of Development
Prototype