Synergism of Interfaces and Defects: Cu/Oxygen Vacancy-Rich Cu-Mn<sub>3</sub>O<sub>4</sub> Heterostructured Ultrathin Nanosheet Arrays for Selective Nitrate Electroreduction to Ammonia
Hongjing Wang, Qiqi Mao, Tianlun Ren, Tongqing Zhou, Kai Deng, Ziqiang Wang, Xiao‐Nian Li, You Xu, Liang Wang
Abstract
Achieving high efficiency in nitrate (NO3–) to ammonia (NH3) electrocatalysis requires the exploration of advanced electrocatalysts with a well-designed composition and architecture. In this work, a facile one-step hydrothermal approach was developed for the construction of novel Cu/oxygen vacancy-rich Cu-Mn3O4 heterostructured ultrathin nanosheet arrays on Cu foam (Cu/Cu-Mn3O4 NSAs/CF). Two-dimensional ultrathin nanosheet arrays could increase the exposure of catalytically active centers, and the heterogeneous nanointerface and oxygen vacancies synergistically improve the nitrate-to-ammonia activity over the active centers. Due to the desirable compositional and structural advantages, the Cu/Cu-Mn3O4 NSAs/CF demonstrated excellent performance for the electrocatalytic nitrate reduction to ammonia with high ammonia selectivity (87.6%) and Faradic efficiency (92.4%).