Aggregation induced edge sites actuation of 3D MoSe₂/rGO electrocatalyst for high-performing water splitting system

Abstract

2D materials are regarded as promising electrocatalysts for water splitting because of their advances in providing ample active sites and improving electrochemical reaction kinetics. 2D MoSe₂ has a greater intrinsic electrical conductivity and lower Gibbs free energy for reactant adsorption. However, there is still room for improvement in the electrocatalytic performance of MoSe₂ for high-performance electrochemical water splitting devices. Herein, the in situ preparation of heterostructure made of covalently bonded MoSe₂ and rGO is reported. The obtained electrocatalyst contains the aggregated 3D structured MoSe₂ over rGO, which is covalently bonded together with more edge sites. The active edge sites of MoSe₂/rGO are dynamically involved in the electrocatalytic activity while facilitating electron transfer. Hence, the MoSe₂/rGO heterostructure requires a low cell voltage of 1.64 V to reach 100 mA cm^-2 in water splitting with high reaction kinetics. The aggregated MoSe₂ over rGO with more edge sites exposed by the 3D structure of MoSe₂ and the interfacial covalent bond in between them provides a favorable electronic structure for the HER and OER with low overpotentials and high current densities and enhances the stability of the electrocatalyst. This work presents an attractive and cost-effective electrocatalyst suitable for industrial-scale hydrogen fuel production.

Keywords

3D/2D heterostructures / aggregation / covalent bond / edge sites / hydrogen production / MoSe₂ / rGO

RIGHTS & PERMISSIONS

2023 2023 The Authors. Aggregate published by South China University of Technology; AIE Institute and John Wiley & Sons Australia, Ltd.