The self-activation and synergy of amorphous Re nanoparticle – Si nanowire composites for the electrocatalytic hydrogen evolution

Amorphous rhenium nanoparticles modified silicon nanowires were prepared via reducing Re ion by Si H bonds, which were employed to electrocatalysize the hydrogen evolution reaction because amorphous structure may have excellent catalytic activity. It is interesting that an obvious self-activation for Re/Si catalysts was observed with the current density enhanced by 2.2 times its previous value at 400   mV after a 3,000   s of continuous cyclic voltammetry scanning, and the catalytic performance remained steady thereafter. The optimal electrocatalytic performance was found with the Re: Si mass ratio of 31.1: 68.9, resulting in a Tafel slope of 81   mV·dec −1 and overpotential of 100   mV at current density of 10   mA·cm −2 .