The CO2 electroreduction reaction (CO2RR) to fuels and feedstocks is an attractive route to close the anthropogenic carbon cycle and store renewable energy. The generation of more reduced chemicals, especially multicarbon oxygenate and hydrocarbon products (C2+) with higher energy densities, is highly desirable for industrial applications. However, selective conversion of CO2 to C2+ suffers from a high overpotential, a low reaction rate and low selectivity, and the process is extremely sensitive to the catalyst structure and electrolyte. Here we discuss strategies to achieve high C2+ selectivity through rational design of the catalyst and electrolyte. Current state-of-the-art catalysts, including Cu and Cu–bimetallic catalysts, as well as some alternative materials, are considered. The importance of taking into consideration the dynamic evolution of the catalyst structure and composition are highlighted, focusing on findings extracted from in situ and operando characterizations. Additional theoretical insight into the reaction mechanisms underlying the improved C2+ selectivity of specific catalyst geometries and compositions in synergy with a well-chosen electrolyte are also provided.
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This work was supported by the European Research Council under grant ERC-OPERANDOCAT (ERC-725915) and the German Federal Ministry of Education and Research (BMBF) under grants #03SF0523C-’CO2EKAT’ and #033RCOO4D-’e-Ethylene’, as well as the German Research Foundation (DFG) - SFB 1316, subproject B1.
The authors declare no competing interests.
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Journal of Energy Chemistry (2020)
Journal of Iron and Steel Research International (2019)
Carbon dioxide electroreduction to C2 products over copper-cuprous oxide derived from electrosynthesized copper complex
Nature Communications (2019)
Accounts of Chemical Research (2019)
Advanced Materials (2019)