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In Situ Reconstruction of V‐Doped Ni 2 P Pre‐Catalysts with Tunable Electronic Structures for Water Oxidation
Author(s) -
Zhao Tingwen,
Shen Xiangjian,
Wang Yuan,
Hocking Rosalie K.,
Li Yibing,
Rong Chengli,
Dastafkan Kamran,
Su Zhen,
Zhao Chuan
Publication year - 2021
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.202100614
Subject(s) - overpotential , materials science , oxygen evolution , catalysis , electrolyte , dopant , nickel , electrochemistry , raman spectroscopy , dielectric spectroscopy , chemical engineering , water splitting , inorganic chemistry , electrode , doping , chemistry , organic chemistry , metallurgy , physics , optoelectronics , photocatalysis , optics , engineering
Nickel‐based electrocatalysts are promising candidates for oxygen evolution reaction (OER) but suffer from high activation overpotentials. Herein, in situ structural reconstruction of V‐doped Ni 2 P pre‐catalyst to form highly active NiV oxyhydroxides for OER is reported, during which the partial dissolution of V creates a disordered Ni structure with an enlarged electrochemical surface area. Operando electrochemical impedance spectroscopy reveals that the synergistic interaction between the Ni hosts and the remaining V dopants can regulate the electronic structure of NiV oxyhydroxides, which leads to enhanced kinetics for the adsorption of *OH and deprotonation of *OOH intermediates. Raman spectroscopy and X‐ray absorption spectroscopy further demonstrate that the increased content of active β‐NiOOH phase with the disordered Ni active sites contributes to OER activity enhancement. Density functional theory calculations verify that the V dopants facilitate the generation of *O intermediates during OER, which is the rate‐determining step for realizing efficient O 2 evolution. Optimization of these properties endows the NiV oxyhydroxide electrode with a low overpotential of 221 mV to deliver a current density of 10 mA cm −2 and excellent stability in the alkaline electrolyte.