摘要
Highly efficient electrocatalysts towards hydrogen evolution reaction(HER) with large current density at all-pH values are critical for the sustainable hydrogen production. Herein, we report a free-standing HER electrode, phosphorous-doped molybdenum nitride nanoparticles embedded in 3-dimentional carbon nanosheet matrix(P-Mo2N-CNS) fabricated via one-step carbonization and in-situ formation. The asprepared catalyst shows free-standing architecture with interconnected porous microstructure. P-doped Mo2N nanoparticles with an average diameter of 4.4 nm are well embedded in the 3-dimentional vertical carbon nanosheets matrix. Remarkable electrocatalytic HER performance is observed in alkaline, neutral and acidic media at large current densities. The overpotential of P-Mo2N-CNS to drive a current density of 100 mA cm-2 in 0.5 M H2SO4 and 1.0 M PBS is only 181 and 221 mV, respectively. In particular, the current density reaches up to 1000 mA cm-2 at a low overpotential of 256 mV in 1.0 M KOH, much better than that of the commercial Pt/C catalyst. Density functional theory calculations suggest the optimized H sorption kinetics on Mo2N after P doping, elucidating the superior activity.
基金
the National Natural Science Foundation of China(Grant Nos.51772089,21872046 and 51902100)
the Outstanding Youth Scientist Foundation of Hunan Province(Grant No.2018JJ1009)
the Youth 1000 Talent Program of China
the Science and Technology Innovation Platform and Talent Plan of Hunan Province(Grant No.2017XK2023)
the Research and Development Plan of Key Areas in Hunan Province(Grant No.2019GK2235)
China Postdoctoral Science Foundation(2018M642971)
the Youth Scientist Foundation of Hunan Province(Grant No.2019JJ50087)
the Shenzhen Science and Technology Innovation Committee(Grant No.JCYJ20151013162733704)。