MoSe₂-Amorphous CNT Hierarchical Hybrid Core–Shell Structure for Efficient Hydrogen Evolution Reaction

Fabrication of noble-metal-free, earth-abundant, inexpensive, and efficient electrocatalyst for hydrogen evolution reaction (HER) is a challenge for clean and sustainable energy carrier. Transition-metal dichalcogenides have shown their potential as an electrode material toward electrochemical HER activity. Herein we successfully developed hierarchical core–shell nanostructure of molybdenum diselenide (MoSe2)-amorphous carbon nanotube (aCNT) via a simple solvothermal procedure, showing excellent electrocatalytic HER activity in acidic medium. The MoSe2-aCNT exhibits onset potential as low as −64 mV and small Tafel slope of ∼49 mV/dec with an HER activity superior to that of the pristine aCNTs and MoSe2. Experimental results along with theoretical investigation demonstrate that the exposed active edges of MoSe2 nanosheet on amorphous wall of the aCNTs with a low free energy barrier promote the improvement of electrocatalytic HER activity. This work opens a new strategy for the development of advanced amorphous carbon nanostructure-based hybrid HER catalyst in acidic medium.