Pitaya-like cobalt/molybdenum carbide encapsulated in N-doped carbon nanospheres toward efficient hydrogen evolution

Abstract

Highly active and stable non-noble metal electrocatalyst for efficient hydrogen evolution reaction (HER) has long been pursued for renewable energy system. Herein, pitaya-like cobalt/molybdenum carbide encapsulated in N-doped carbon nanospheres (CoMoCx@NC) have been synthesized through a facile organic-inorganic carbonization method. The organic polyaniline/pyrrole can effectively prevent active CoMoCx nanoparticles from aggregation and the formed ultrathin carbon layers during carbonization process can prevent active CoMoCx nanoparticles from corrosion during the HER process. The resulting CoMoCx@NC exhibits excellent HER performance and long-term stability for HER in both acidic and alkaline solutions. The excellent HER activity is attributed to the synergistic effect among Mo2C, Co, and N-doped carbon, the high conductivity of carbon matrix, and ultrathin carbon layer encapsulation in the CoMoCx@NC nanospheres.