Ni─Co─O─S Derived Catalysts on Hierarchical N‐doped Carbon Supports with Strong Interfacial Interactions for Improved Hybrid Water Splitting Performance
Yunfeng Qiu, Yongxia Zhang, Miao Yu, Xinyi Li, Yanxia Wang, Zhuo Ma, Shaoqin Liu
Abstract
Abstract Simultaneously improving electrochemical activity and stability is a long‐term goal for water splitting. Herein, hierarchical N‐doped carbon nanotubes on carbon nanowires derived from PPy are grown on carbon cloth, serving as a support for NiCo oxides/sulfides. The hierarchical electrodes annealed in N 2 or H 2 /N 2 display improved intrinsic activity and stability for hydrogen evolution reaction (HER) and glucose oxidation reaction. Compared with Pt/C||Ir/C in alkaline media, the glucose electrolysis assembled with electrodes exhibits a cell voltage of 1.38 V at 10 mA cm −2 , durability for >12 h at 50 mA cm −2 , and resistance to glucose/gluconic acid poisoning. In addition, electrocatalysts can also be applied in ethanol oxidation reactions. Systematic characterizations reveal the strong interactions between NiCo and N‐doped carbon support‐induced partial charge transfer at the interface and regulate the local electronic structure of active sites. Density functional theory calculations demonstrate that the synergistic effect between N‐doped carbon supports, metallic NiCo, and NiCo oxides/sulfides optimize the adsorption energy of H 2 O and the H* free energy for HER. The energy barrier of the dehydrogenation of glucose effectively decreased. This work will attract attention to the role of metal‐support interactions in enhancing the intrinsic activity and stability of electrocatalysts.