Modulating Electronic Structure by Etching Strategy to Construct NiSe<sub>2</sub>/Ni<sub>0.85</sub>Se Heterostructure for Urea‐Assisted Hydrogen Evolution Reaction
Kaili Wu, Chaojie Lyu, Jiarun Cheng, Zhonglu Guo, Hongyu Li, Xixi Zhu, Woon‐Ming Lau, Jinlong Zheng
Abstract
Abstract Exploring and developing novel strategies for constructing heterostructure electrocatalysts is still challenging for water electrolysis. Herein, a creative etching treatment strategy is adopted to construct NiSe 2 /Ni 0.85 Se heterostructure. The rich heterointerfaces between NiSe 2 and Ni 0.85 Se emerge strong electronic interaction, which easily induces the electron transfer from NiSe 2 to Ni 0.85 Se, and tunes the charge‐state of NiSe 2 and Ni 0.85 Se. In the NiSe 2 /Ni 0.85 Se heterojunction nanomaterial, the higher charge‐state Ni 0.85 Se is capable of affording partial electrons to combine with hydrogen protons, inducing the rapid formation of H 2 molecule. Accordingly, the lower charge‐state NiSe 2 in the NiSe 2 /Ni 0.85 Se heterojunction nanomaterial is more easily oxidized into high valence state Ni 3+ during the oxygen evolution reaction (OER) process, which is beneficial to accelerate the mass/charge transfer and enhance the electrocatalytic activities towards OER. Theoretical calculations indicate that the heterointerfaces are conducive to modulating the electronic structure and optimizing the adsorption energy toward intermediate H * during the hydrogen evolution reaction (HER) process, leading to superior electrocatalytic activities. To expand the application of the NiSe 2 /Ni 0.85 Se‐2h electrocatalyst, urea is served as the adjuvant to proceed with the energy‐saving hydrogen production and pollutant degradation, and it is proven to be a brilliant strategy.