摘要
Electrochemical water splitting powered by green electricity generated from intermittent geothermal, wind and solar power is a promising approach to realize large-scale hydrogen production owing to its sustainable and clean characteristics. Developing electrocatalysts with high electrocatalytic activity and long-term stability for the hydrogen evolution reaction (HER) at an ultrahigh current density (> 1000 mA cm(-2)) still needs a breakthrough. Here, a bicontinuous nanoporous PtNiMg alloy with an ultralow noble metal content for the HER is fabricated by a facile high-temperature sintering method based on the nanoscale Kirkendall effect. A bicontinuous nanoporous alloy electrode with an ultralow content of approximately 1 at % Pt for the HER in an alkaline medium achieves an extremely low overpotential of 22 mV at a current density of 10 mA cm(-2) and a Tafel slope (30.9 mV dec(-1)) of the Volmer-Tafel mechanism. The alloy electrode for the HER at a wide current density of 1-2000 mA cm(-2) displays superior stability in alkaline media. The 3D bicontinuous nanoporous structure, perfect synergistic effect of Ni and Pt species, high structural stability and excellent conductivity of the 1-PtNiMg-900 alloy achieve outstanding electrocatalytic activity and long-term stability at an ultrawide range of HER current densities. This study greatly improves the electrochemical performance of Pt-based electrocatalysts for the HER via a novel fabrication approach and provides the possibility of large-scale industrial application for H-2 production.
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单位南昌航空大学