Electron density modulation of NiCo₂S₄ nanowires by nitrogen incorporation for highly efficient hydrogen evolution catalysis.

ABSTRACT: Metal sulfides for hydrogen evolution catalysis typically suffer from unfavorable hydrogen desorption properties due to the strong interaction between the adsorbed H and the intensely electronegative sulfur. Here, we demonstrate a general strategy to improve the hydrogen evolution catalysis of metal sulfides by modulating the surface electron densities. The N modulated NiCo₂S₄ nanowire arrays exhibit an overpotential of 41 mV at 10 mA cm^-2 and a Tafel slope of 37 mV dec^-1, which are very close to the performance of the benchmark Pt/C in alkaline condition. X-ray photoelectron spectroscopy, synchrotron-based X-ray absorption spectroscopy, and density functional theory studies consistently confirm the surface electron densities of NiCo₂S

SUBMITTER: Wu Y 

PROVIDER: S-EPMC5897358 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature