Steering CO2 electroreduction toward methane or ethylene production

Highly selective production of valuable hydrocarbons from CO2 electroreduction is particularly desirable yet challenging. Herein we steer CO2 electroreduction toward methane (CH4) or ethylene (C2H4) production with high selectivity by controlling the loading of copper phosphate (Cu3(PO4)2) nanosheets on electrode. The low loading (0.28 mg cm-2) and high loading (2.24 mg cm-2) of Cu3(PO4)2 nanosheets lead to Faradaic efficiency of 76% for CH4 and 67% for C2H4, respectively. Mechanism investigation reveals that metallic Cu nanoparticles are derived during electrolysis at low Cu3(PO4)2 loading condition, favoring *CO hydrogenation to CH4 production. At high Cu3(PO4)2 loading condition, the metallic Cu nanoparticles decorated with Cu3(PO4)2 are produced, which can stabilize and promote the dimerization of *CO to C2H4 formation. This work provides new insights into controlling the electrocatalytic CO2 reduction from C1 to C2 products by designing derivatives of Cu-based catalyst.