▎ 摘　　要

A highly active, stable and inexpensive electrocatalyst, nanosized-Mo2C/reduced-graphene-oxide (nanoMo(2)C/RGO), is developed for the hydrogen evolution reaction, which is of vital importance for environment concerns and the energy crisis. The nanocomposite catalyst is synthesized by a novel strategy through the facile calcination of a pre-prepared organic-inorganic hybrid MoOx-amine precursor of sub-nanosized periodic structure. The intercalation of the amine in the organic-inorganic precursor leads to the synchronous reduction of MoOx-amine to Mo2C and GO to RGO in an inert atmosphere, and thus nano-Mo2C/RGO is facilely synthesized with highly monodisperse Mo2C nanoparticles (3-5nm) as well as the reduced graphene. The remarkable structures and features are demonstrated to be the determinants for accelerating the interfacial electrocatalytic reaction with low charge-transfer resistance and high interfacial capacitance. This study should provide a new perspective on the development of efficient noble-metal-free electrocatalysts in the fields of energy conversion and storage.