Progresses on carbon dioxide electroreduction into methane

The conversion of CO2 into value-added chemicals and fuels via electrochemical methods paves a promising avenue to mitigate both energy and environmental crisis. Among all the carbonaceous products derived from CO2 electroreduction, CH4 is one of the most important carriers for chemical bond energy storage due to the highest value of mass heat. Herein, starting from the proposed reaction mechanisms reported previously, we summarized the recent progresses on CO2 electroreduction into CH4 from the perspective of catalyst design strategies including construction of sub-nanometer catalytic sites, modulation of interfaces, in-situ structural evolution, and engineering of tandem catalysts. On the basis of both the previously theoretical predictions and experimental results, we aimed to gain insights into the reaction mechanism for the formation of CH4, which, in turn, would provide guidelines for the design of highly efficient catalysts.