Tungsten carbides have attracted wide attentions as Pt substitute electrocatalysts for hydrogen evolution reaction(HER),due to their good stability in an acid environment and Pt-like behaviour in hydrolysis.However,quantum chemistry calculations predict that the strong tungsten-hydrogen bonding hinders hydrogen desorption and restricts the overall catalytic activity.Synergistic modulation of host and guest electronic interaction can change the local work function of a compound,and therefore,improve its elec-trocatalytic activity over either of the elements individually.Herein,we develop a creative and facile solid-state approach to synthesize self-supported carbon-encapsulated single-phase WC hybrid nano-wires arrays(nanoarrays)as HER catalyst.The theoretical calculations reveal that carbon encapsulation modifies the Gibbs free energy of H* values for the WC adsorption sites,endowing a more favorable C@WC active site for HER.The experimental results exhibit that the hybrid WC nanoarrays possess remarkable Pt-like catalytic behavior,with superior activity and stability in an acidic media,which can be compared to the best non-noble metal catalysts reported to date for hydrogen evolution reaction.The present results and the facile synthesis method open up an exciting avenue for developing cost-effective catalysts with controllable morphology and functionality for scalable hydrogen generation and other carbide nanomaterials applicable to a range of electrocatalytic reactions.