Construction of 3D Ni3Se2@NiCo-LDH heterostructured system for efficient electrocatalytic oxygen evolution reaction

Abstract

Heterointerface engineering is an effective technique for synthesizing highly efficient catalysts that may synergize the advantages of each component to enhance their catalytic activity. This study developed a heterostructured Ni3Se2 @NiCo-LDH system, in which NiCo-LDH nanosheets are electrodeposited on hydrothermally-grown pine tree-like Ni3Se2 structures. The Ni3Se2 @NiCo-LDH heterostructured electrode exhibits a remarkably low overpotential (140 mV) for oxygen evolution reaction (OER) activity at a current density of 10 mA/cm2, which was attributed to the enhanced electrochemical properties of the interface owing to the high conductivity of Ni3Se2 and the high intrinsic OER activity of NiCo-LDH. In addition, the unusual pine tree-branched Ni3Se2 structure with NiCo-LDH nanosheets enabled the generation of additional active sites at the heterointerface, which exhibited enhanced oxygen evolution capability, with a strong electron connection from Ni and Co and an active synergistic contribution from selenide. Additionally, after 20 h of electrolysis in 1.0 M KOH, the catalyst maintained 98.8 % of its initial current density. The findings of this study is expected to set the path for the production of further heterostructure electrocatalysts.