Nano-porous Mo 2 C in-situ grafted on macroporous carbon electrode as an efficient 3D hydrogen evolution cathode

Abstract

The development of low-cost, scalable and realistic electrodes with robust catalytic activity and stability remains a great challenge for large-scale hydrogen production from electrochemical water splitting. Herein, we firstly reported a 3D self-supported porous hydrogen evolution cathode constructed by in-situ growth of nano-porous molybdenum carbide (Mo2C) nanoflakes on a commercial graphite felt (GF) through a facile electrostatic self-assembly followed by high-temperature carburization approach. Owing to a synergistic effect from high activity of nano-porous Mo2C and rich macroporous architecture of GF for fast diffusion of electrolyte and generated hydrogen bubbles, the 3D Mo2[email protected] hybrid electrode only needs a low overpotential of 124 and 129 mV to deliver a cathodic current density of 10 mA cm−2 in 0.5 M H2SO4 and 1 M KOH solution, respectively. Particularly, the strong incorporation of nano-Mo2C onto graphite fibers promotes interfacial electron transfer and enables superior stability and durability in both acidic and basic electrolyte. This work provides a proof of concept and design rules for developing truly workable electrodes with promising potential in practical hydrogen evolution.