Tailoring the d-Band Centers Enables Co4N Nanosheets To Be Highly Active for Hydrogen Evolution Catalysis

Endowing materials with specific functions that are not readily available is always of great importance, but extremely challenging. Co4N, with its beneficial metallic characteristics, has been proved to be highly active for the oxidation of water, while it is notoriously poor for catalyzing the hydrogen evolution reaction (HER), because of its unfavorable d-band energy level. Herein, we successfully endow Co4N with prominent HER catalytic capability by tailoring the positions of the d-band center through transition-metal doping. The V-doped Co4N nanosheets display an overpotential of 37mV at 10mAcm(-2), which is substantially better than Co4N and even close to the benchmark Pt/C catalysts. XANES, UPS, and DFT calculations consistently reveal the enhanced performance is attributed to the downshift of the d-band center, which helps facilitate the H desorption. This concept could provide valuable insights into the design of other catalysts for HER and beyond.