New insight on hydrogen evolution reaction activity of the most exposure (0 1 1) surface and its monovacancy defect for FeP system: A theoretical perspective

We systemically investigated the hydrogen evolution reaction (HER) catalytic activity for the most exposure (0 1 1) surface and its monovacancy defect for FeP system using periodic density functional theory (DFT). The calculated values of adsorption free energy of H* (ΔGH*) reveal that (0 1 1) surface has high HER catalytic activity. In addition, the formation of monovacancy defect with Fe or P at (0 1 1) surface keeps good HER catalytic activity. We hope this letter can shed new light on further understanding HER in relation to FeP system and give guidance for design of transition metal phosphides.