An Atomically Dispersed Pt Catalyst Anchored on an Fe/N/C Support for Enhanced Hydrogen Evolution Reaction

A highly efficient Pt-Fe/N/C catalyst with an ultralow Pt loading of 1.5 wt % is designed and synthesized based on a special iron and nitrogen co-doped carbon support (Fe/N/C). High-angle annular dark-field scanning transmission electron microscopy and extended X-ray absorption fine structure prove that the Pt is atomically dispersed in the Pt-Fe/N/C catalysts, leading to a high Pt utilization. The electrochemical results indicate that this Pt-Fe/N/C catalyst exhibits an excellent hydrogen evolution reaction (HER) performance, with a low overpotential of 51 mV at the current density of 10 mA cm–2 and a small Tafel slope of 48 mV dec–1, which are comparable with that of 20 wt % Pt/C. The enhanced performance can be ascribed to the intensive electron transfer between Pt atoms and the Fe and N co-doped substrate, resulting in an enhanced HER intrinsic activity. Furthermore, the Pt-Fe/N/C catalysts are applied as the cathode catalysts for water electrolysis, which exhibits an excellent performance of a low cell voltage of ∼1.8 V at 1 A cm–2 and a good stability for 100 h of continuous hydrogen production when the cathode Pt loading is reduced to only 4 μg cm–2. The study provides a general strategy to develop Pt atomically anchored electrocatalysts with low cost, high activity, and high stability.