Microwave-Assisted Synthesis of Copper-Based Electrocatalysts for Converting Carbon Dioxide to Tunable Syngas

Copper (Cu)-based materials for efficient CO2 conversion to adjustable syngas are reported. We employ an energy-efficient microwave-assisted route to synthesize copper/copper oxides with different structures and morphologies. The initial oxidation state of the copper on the surface significantly influences the performance of the materials in the CO2 reduction reaction (CO2RR). On the as-prepared material surface, a high content of Cu2O improves the selectivity toward CO and consequently the catalyzed CO2RR produce a syngas with a low H-2/CO ratio, while the CuO performs poorly. In particular, Cu2O particles with a cubic shape show the highest selectivity for the CO formation. The superior catalytic activity of the Cu2O cubes for the CO2RR is attributed to the surface roughening under potential, which offers abundant electrochemically active sites and facilitates mass transport.