Nickel and indium core-shell co-catalysts loaded silicon nanowire arrays for efficient photoelectrocatalytic reduction of CO2 to formate

Abstract

Abstract Developing an efficient artificial photosynthetic system for transforming carbon dioxide and storing solar energy in the form of chemical bonds is one of the greatest challenges in modern chemistry. However, the limited choice of catalysts with wide light absorption range, long-term stability and excellent selectivity for CO2 reduction makes the process sluggish. Here, a core-shell-structured non-noble-metal Ni@In co-catalyst loaded p-type silicon nanowire arrays (SiNWs) for efficient CO2 reduction to formate is demonstrated. The formation rate and Faradaic efficiency of formate over the Ni@In/SiNWs catalyst reach 58 μmol h−1 cm−2 and 87% under the irradiation of one simulated sunlight (AM 1.5G, 100 mW cm−2), respectively, which are about 24 and 12 times those over the pristine SiNWs. The enhanced photoelectrocatalytic performance for CO2 reduction is attributed to the rational combination of Ni capable of effectively extracting the photogenerated electrons and In responsible for the selective activation of CO2.