Interfacial engineering-triggered electronic regulation of Re and CoP hollow multi-shelled structure toward high-activity electrochemical water splitting

Abstract

Exploring high-activity and affordable bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of great importance in the development of water electrolysis. Herein, an advanced heterostructured electrocatalyst consisting of Re and CoP with a hollow multi-shelled structure (abbreviated hereafter as Re/CoP HoMS) is established through an electrostatic spray-assisted strategy. Experimental data and theoretical simulation disclose that the construction of a Re/CoP heterostructure can powerfully modify the electronic state at the interface, promote the electron migration rate, and regulate water dissociation and intermediates adsorption abilities. Consequently, the harvested Re/CoP HoMS with optimal Re content displays excellent HER and OER performance with overpotentials of 107 and 239 mV to afford 10 mA cm⁻², Tafel slopes of 89.4 and 116.7 mV dec⁻¹, and i–t tests of 33 and 50 h, respectively. More encouragingly, a two-electrode system assembled from Re/CoP HoMS exhibits more impressive electrochemical performance in comparison with a state-of-the-art Pt/C//RuO₂ reference and also possesses outstanding stability and reversibility, suggesting enormous potential for large-scale H₂ production.