Low‐Coordinated Edge Sites on Ultrathin Palladium Nanosheets Boost Carbon Dioxide Electroreduction Performance

Abstract

AbstractElectrochemical conversion of carbon dioxide (CO2) to value‐added products is a possible way to decrease the problems resulting from CO2 emission. Thanks to the eminent conductivity and proper adsorption to intermediates, Pd has become a promising candidate for CO2 electroreduction (CO2ER). However, Pd‐based nanocatalysts generally need a large overpotential. Herein we describe that ultrathin Pd nanosheets effectively reduce the onset potential for CO by exposing abundant atoms with comparatively low generalized coordination number. Hexagonal Pd nanosheets with 5 atomic thickness and 5.1 nm edge length reached CO faradaic efficiency of 94 % at −0.5 V, without any decay after a stability test of 8 h. It appears to be the most efficient among all of Pd‐based catalysts toward CO2ER. Uniform hexagonal morphology made it reasonable to build models and take DFT calculations. The enhanced activity originates from mainly edge sites on palladium nanosheets.