Enriched edge sites of ultrathin Ni3S2/NiO nanomeshes promote surface reconstruction for robust electrochemical water splitting

作者：Min Zhao, Jingkun Wang, Chengqiang Wang, Ying Sun, Peizhi Liu, Xiaoqiang Du, Hongge Pan, Hui Li, Haojie Liang, Junjie Guo, Tianyi Ma · 发表于：Nano Energy · 年份：2024 · DOI：10.1016/j.nanoen.2024.110020 · 被引用次数：89 · 研究领域：Electrocatalysts for Energy Conversion、Advanced Photocatalysis Techniques、Advanced battery technologies research

Developing highly efficient nonnoble bifunctional electrocatalysts for both the H2 evolution reaction (HER) and O2 evolution reaction (OER) is essential but challenging for overall water splitting (OWS). Ni based catalysts are proved as promising candidates for water splitting, which usually undergo surface reconstruction by transforming into nickel oxyhydroxides as active sites. Although evidence suggests that the reconstruction originates from the exchange of surface lattice oxygen with the OH- in the electrolyte under electric field, modulating the reconstruction of Ni based catalysts remains a great challenge. Herein, we propose an edge sites enrichment strategy to promote the active phase evolution. The one-step synthesized ultrathin Ni3S2/NiO nanomeshes exhibited an ultrathin porous structure which contain abundant edge sites and Ni3S2/NiO in-plane interface sites. Owing to the unique structure, Ni3S2/NiO nanomeshes possessed an affinity feature to proton and OH-, resulting in a faster reconstruction from Ni3S2 to Ni(OH)2 than Ni3S2 bulk which subsequently converted into γ-NiOOH and a lower adsorption barrier for H*. Consequently, the Ni3S2/NiO nanomeshes exhibited outstanding OER activity (300 mV at 200 mA cm−2) and unexpected HER activity (73 mV at 10 mA cm−2) in 1.0 M KOH. Remarkably, the nanomeshes achieved an ultralow voltage of 1.41 V at 10 mA cm−2 with excellent stability for overall water splitting, which prevailed over most of the reported catalysts. Moreover, ...