Construction of pH-universal hydrogen evolution freeway in MoO3-MoNi4@Cu core–shell nanowires via synergetic electronic and geometric effect.

Both the adsorption/dissociation of water molecules and hydrogen intermediate (H*) are the major limitations to hydrogen evolution reaction (HER). Herein, the modulation of electronic structure and geometric configuration are combined to design one-dimensional electrocatalyst with outstanding HER activity in a wide pH range. The catalyst was composed of molybdenum trioxide doped molybdenum nickel alloy supported by copper nanowires (MoO₃-MoNi₄@Cu NWs). As revealed by the experimental characterizations and theoretical calculations, Cu NWs act as the electron donator to MoNi₄, resulting in up shift of the d-band center in MoNi₄, thus expediting H₂O adsorption and dissociation. Moreover, the introduction of amorphous MoO₃ sets up a unique geometric configuration on MoNi₄ for the accelerated H* transfer via hydrogen-bond and hydrogen spillover. This work provides a synergetic route for constructing HER freeway and promotes further investigations on more versatile electrocatalysis involving H₂O or H*. [ABSTRACT FROM AUTHOR]