One-pot hydrothermal synthesis and selective etching method of a porous MoSe2 sand rose-like structure for electrocatalytic hydrogen evolution reaction

Abstract

The development of a platinum-free electrocatalyst for the hydrogen evolution reaction (HER) is highly essential to the large-scale production and application of water splitting devices. Herein we report a facile one-pot hydrothermal synthesis of composite MoSe₂@Cu₂Se. The morphology of the obtained material was characterized by scanning electron microscope (SEM) and it was found that the composite material formed a sand rose-like structure. The crystal structure and phase purity of the composite MoSe₂@Cu₂Se were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Then a selective electrochemical etching of copper from the composite was carried out and the porous MoSe₂ rose-like nanosphere was obtained. The robust 3D MoSe₂ rose-like structure exhibit remarkable activity and durability for electrocatalytic HER in acid maintaining a small onset overpotential of ∼150 mV and keeping a small overpotential of 300 mV for 6 mA cm⁻² current density after 1000 cycles. Based on our data, the obtained porous sand rose-like structure material could improve the active surface area which yields higher HER catalytic activity. The present study provides a simple and effective way for the exploration of efficient Mo-based HER catalysts.