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

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 nonnoble-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 mu mol 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. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

The development of an efficient artificial photosynthetic system for CO2 reduction is a significant challenge in modern chemistry. By using a core-shell-structured nonnoble-metal Ni@In co-catalyst, the photoelectrocatalytic performance for CO2 reduction is greatly enhanced, leading to higher formation rate and Faradaic efficiency of formate compared to pristine SiNWs. This improvement is attributed to the rational combination of Ni and In for effective extraction of photogenerated electrons and selective activation of CO2.