Phase Engineering of Molybdenum Carbide/Oxide for Highly-Efficient Electrocatalytic Hydrogen Production.

Molybdenum carbide is one of non-precious metal materials and it is a promising electrocatalyst for hydrogen production. Synthesis and improvement of molybdenum carbide's catalytic performance is of great significance. Herein, carbon-based Mo2C with hybrid phase of MoO2 was fabricated by matching the composition of Mo and C derived from pomelo peel and optimizing raw carbon amount and prolysis temperature. The resulting MoO2/Mo2C@C is composed of loose microspheres with mesoporous microstructure and is self-assembled from nanoparticles. The results show that MoO2/Mo2C@C2 material exhibits excellent HER performance and only a low overpotentials of 143 mV is needed to drive the current density of 10 mA cm-2 in alkaline solution, and Tafel slopes are only 63.4 mV dec-1, respectively. Notably, it has potential application at low overpotentials to drive large current density and this strategy also provides a universal route to prepare non-noble metal catalyst with hybrid phase of oxide/carbide.