<i>In-Situ</i> Surface Reconstruction of InN Nanosheets for Efficient CO₂ Electroreduction into Formate.

Abstract

Probing and understanding the intrinsic active sites of electrocatalysts is crucial to unravel the underlying mechanism of CO₂ electroreduction and provide a prospective for the rational design of high-performance electrocatalysts. However, their structure-activity relationships are not straightforward because electrocatalysts might reconstruct under realistic working conditions. Herein, we employ <i>in-situ</i> measurements to unveil the intrinsic origin of the InN nanosheets which served as an efficient electrocatalyst for CO₂ reduction with a high faradaic efficiency of 95% for carbonaceous product. During the CO₂ electroreduction, InN nanosheets reconstructed to form the In-rich surface. Density functional theory calculations revealed that the reconstruction of InN led to the redistribution of surface charge that significantly promoted the adsorption of HCOO* intermediates and thus benefited the formation of formate toward CO₂ electroreduction. This work establishes a fundamental understanding on the mechanism associated with self-reconstruction of heterogeneous catalysts toward CO₂ electroreduction.