Nitrogen, phosphorus dual-doped molybdenum-carbide/molybdenum-phosphide-@-carbon nanospheres for efficient hydrogen evolution over the whole pH range.

MoO@aniline-pyrrole (MoO@polymer) spheres as precursors have been used to synthesize unique core-shell nanostructure consisting of molybdenum carbide and molybdenum phosphide composites encapsulated into uniformly dual N, P-doped carbon shells (MoC/MoP@NPC) through a facile two-step strategy. Firstly, porous core-shell N-doped MoC@C (MoC@NC) nanospheres have been synthesized with ultrafine MoC nanoparticles as core and ultrathin NC as shell by a annealing route. Secondly, MoC/MoP@NPC has been obtained maintaining intact spherical-like morphology through a phosphidation reaction in high temperature. The synergistic effect of MoC and MoP may reduce the strong MoH bonding energy of pure MoC and provide a fast hydrogen release process. In addition, the dual N, P-doped carbon matrix as shell can not only improve the electroconductivity of catalysts but also prevent the corrosion of MoC/MoP nanoparticles during the electrocatalytic process. When used as HER cathode in acids, the resulting MoC/MoP@NPC shows excellent catalytic activity and durability, which only needs an overpotential of 160 mV to drive 10 mA cm. Moreover, it also exhibits better HER performance in basic and neutral media with the need for overpotentials of only 169 and 228 mV to achieve 10 mA cm, respectively. This inorganic-organic combination of Mo-based catalysts may open up a new way for water-splitting to produce large-scale hydrogen.