Accelerating Neutral Hydrogen Evolution with Tungsten Modulated Amorphous Metal Hydroxides

Developing efficient, low-cost, and biocompatible electrocatalysts toward hydrogen evolution reaction (HER) in neutral environments is vital to the development of a hybrid water splitting–biosynthetic system to achieve high-efficiency solar-to-fuels conversion. We report here a strategy to improve the sluggish HER kinetics on 3d transition-metal hydroxides by incorporating tungsten through a one-step electrodeposition method. The prepared amorphous CoW(OH)x delivers high HER activity in neutral solution, which only requires overpotentials of −73.6 and −114.9 mV to achieve the current densities of −10 and −20 mA cm–2 in 1.0 M phosphate buffer solution (PBS), respectively. The activity can be ascribed to the synergistic effects between Co and W, where Co sites facilitate H2O dissociation to generate Had intermediates and W sites could effectively convert Had to H2. Meanwhile, the amorphous architecture features homogeneously dispersed Co and W atoms that avoid crystalline phase separation, further strengthe...