A Rational Design of Cu2O-SnO2 Core-Shell Catalyst for Highly Selective CO2-to-CO Conversion

The electrochemical reduction of CO2 (CO2RR) is a versatile method that is capable of simultaneously reduce CO2 emission and produce valuable fuels and chemicals. However, its application is hindered by the lack of cost-effective catalysts and significant overpotential requirement. In this work, we report a low-cost and surfactant/capping agent free method to synthesize cubic Cu2O SnO2 core-shell electrocatalyst, whose thickness can be easily controlled by the content of tin precursor. The optimized Cu2O SnO2 catalyst with a 5 nm-thick shell achieved over 90% faradaic efficiency towards CO at a low overpotential of 390 mV, which is comparable to some of the noble metal catalysts. The catalyst also exhibited good stability over 18 hours of test at 0.6 V vs. RHE in 0.5 M KHCO3 electrolyte. This work provides a widely applicable strategy for developing a low-cost electrocatalyst for CO2 conversion.