Construction of Ni2p-Nife2o4 Heterostructured Nanosheets Towards Performance-Enhanced Water Oxidation Reaction

Abstract

Water electrolysis represents a promising option for clean hydrogen production, but its overall efficiency is hindered by the sluggish oxygen evolution reaction (OER) with a complex electron transfer process. The construction of heterostructure has emerged as an effective approach to enhance the electrocatalytic performance for OER because of the improvement of exposed active surface and mass/charge transfer. In this work, we report the synthesis of hierarchical nanosheet-structured Ni2P-NiFe2O4 as a robust OER catalyst via an annealing treatment and followed by in-situ phosphating process. The Ni2P-NiFe2O4 electrocatalyst exhibits an overpotential of 305 mV to realize 100 mA cm-2 in 1.0 M KOH. Density functional theory calculations further confirm that the construction of heterostructure could optimize adsorption energy of oxygen-containing intermediates and reduce energy barrier during the OER process. This work may provide insights into the electrocatalytic activities of non-noble-metal-based catalysts and present an effective method for the preparation of complex structures.

Keywords: Heterostructured nanosheets
In-situ phosphorizationOxygen evolution reaction (OER)DFT calculations