Observation of a robust catalyst support based on metallic glass for large current-density water electrolysis†
Abstract
Support materials such as activated carbon are essential for electrochemical heterogeneous reactions, providing a stable matrix for metal catalysts and actively influencing the catalyst's properties and effectiveness. Although various effective carbon supports have been commercially developed, corrosion and catalyst degradation are still inevitable under high current density catalysis, for instance, during the harsh alkaline water electrolysis process. Here, we report the synthesis of a new type of metallic glass (MG) support through the deployment of an amorphous alloy with tunable Pt loading mass (Fe70−xCo10Ni10Zr10Ptx, x = 1, 3, 5). In addition to the advantages of high specific surface areas and enhanced chemical stability, X-ray absorption spectroscopy and theoretical investigations suggest that the MG support could modulate the electronic structure of Pt active sites through strong metal–support interaction, leading to the enhanced water dissociation kinetics. When compared with those previously reported carbon-supported or pure Pt catalysts, the MG-supported catalysts exhibit remarkably high activities towards hydrogen evolution, which only requires an overpotential of 102 mV at the current density of 1000 mA cm−2 with a Faraday efficiency close to 100%. This allows the current density to be increased to 500 mA cm−2 during the stability test without corrosion and degradation. We argue that the earth-abundant elements-based MG support could be an alternative for metal catalysts that can withstand the physical and chemical corrosion encountered during harsh catalytic reactions.