Highly efficient and robust catalysts for the hydrogen evolution reaction by surface nano engineering of metallic glass†
Abstract
Efficiency and stability are the key parameters for the hydrogen evolution reaction (HER) of water electrolysis, and therefore developing effective and robust catalysts has been a long standing pursuit. In this work, we propose a flexible and universal strategy to synthesize catalysts with excellent HER catalytic performance. Following this strategy, we successfully fabricate a hybrid electrocatalyst by decorating Pt particles on a nano engineered metallic glass (MG) surface (Pt@MG NWs). The overpotential of the catalyst to achieve a geometric current density of 10 mA cm−2 is 48.5 mV in 0.5 M H2SO4. Astonishingly, the Tafel slope is only 19.8 mV dec−1, smaller than that of commercial 10% Pt/C. The Pt@MG NWs exhibit excellent charge transport efficiency and contain around 3 times more active sites than 10% Pt/C. In addition, the Pt@MG NWs are ultra-stable, exhibiting no degradation after the HER at overpotentials of 48.5 mV and 84 mV for 20 hours. Furthermore, this catalyst shows enhanced catalytic performance when a large working current is applied at an overpotential of 200 mV for 500 hours. The hydrophilicity and aerophobicity of Pt@MG NWs, which originate from surface structural construction, are responsible for the outstanding HER catalytic performance. The calculations found that the hybrid electrocatalyst exhibits small Gibbs free energy and strong H2O adsorption energy. Our results provide a novel and universal approach for designing superior HER catalysts with excellent activity and stability.