Vertical Cu Nanoneedle Arrays Enhance the Local Electric Field Promoting C<sub>2</sub> Hydrocarbons in the CO<sub>2</sub> Electroreduction
Yajiao Zhou, Yanqing Liang, Junwei Fu, Kang Liu, Qin Chen, Xiqing Wang, Hongmei Li, Li Zhu, Junhua Hu, Hao Pan, Masahiro Miyauchi, Liangxing Jiang, Emiliano Cortés, Min Liu
Abstract
Electrocatalytic reduction of CO2 to multicarbon products is a potential strategy to solve the energy crisis while achieving carbon neutrality. To improve the efficiency of multicarbon products in Cu-based catalysts, optimizing the *CO adsorption and reducing the energy barrier for carbon–carbon (C–C) coupling are essential features. In this work, a strong local electric field is obtained by regulating the arrangement of Cu nanoneedle arrays (CuNNAs). CO2 reduction performance tests indicate that an ordered nanoneedle array reaches a 59% Faraday efficiency for multicarbon products (FEC2) at −1.2 V (vs RHE), compared to a FEC2 of 20% for a disordered nanoneedle array (CuNNs). As such, the very high and local electric fields achieved by an ordered Cu nanoneedle array leads to the accumulation of K+ ions, which benefit both *CO adsorption and C–C coupling. Our results contribute to the design of highly efficient catalysts for multicarbon products.