MoC Quantum Dots@N‐Doped‐Carbon for Low‐Cost and Efficient Hydrogen Evolution Reaction: From Electrocatalysis to Photocatalysis

Abstract

AbstractSustainable and highly efficient non‐noble metal catalysts could facilitate the realization of closed‐loop and carbon‐neutral hydrogen (H2) economy via low‐cost electrocatalytic (EC) or photocatalytic (PC) H2 evolution reaction (HER) from water. Herein, molybdenum carbide (MoC) quantum dots onto N‐doped porous carbon are in situ synthesized and immobilized, resulting in a bifunctional catalyst MoC@NC. Density functional theory calculation suggests that the targeted catalyst has a suitable Gibbs free‐energy (ΔGH*) for the adsorption of atomic hydrogen, which is beneficial to both EC and PC HERs. For EC HER, the as‐prepared MoC@NC catalyst delivers a low overpotential of 160 mV at −10 mA cm−2 and a remarkable H2 evolution rate in alkaline electrolytes. For PC HER, MoC@NC couple with 2D graphitic carbon nitride (g‐C3N4), which significantly reduces the PC HER energy barrier and enhances the separation efficiency of photogenerated carriers, and consequently, achieves an outstanding photocatalytic H2 evolution rate of 1709 µmol h−1 g−1, which is 213‐fold of that of pure g‐C3N4. This study paves a new avenue for developing sustainable non‐noble metal catalysts for both EC and PC HERs.