Affiliation:
1. Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and Environment Southeast University Nanjing Jiangsu 210096 P. R. China
2. Institute of Chemical Sciences and Engineering École Polytechnique Fédérale de Lausanne (EPFL) Lausanne CH‐1015 Switzerland
3. Engineering Laboratory of Energy System Process Conversion and Emission Reduction Technology of Jiangsu Province School of Energy & Mechanical Engineering Nanjing Normal University Nanjing 210046 P. R. China
Abstract
AbstractIron/iron phosphide nanospheres supported on ginkgo leaf‐derived carbon (Fe&FeP@gl‐C) are prepared using a post‐phosphidation approach, with varying amounts of iron (Fe). The activity of the catalysts in the hydrogen evolution reaction (HER) outperforms iron/iron carbide nanospheres supported on ginkgo leaf‐derived carbon (Fe&FexC@gl‐C), due to enhanced work function, electron transfer, and Volmer processes. The d‐band centers of Fe&FeP@gl‐C‐15 move away from the Fermi level, lowering the H2 desorption energy and accelerating the Heyrovsky reaction. Density functional theory (DFT) calculations reveal that the hydrogen‐binding free energy |ΔGH*| value is close to zero for the Fe&FeP@gl‐C‐15 catalyst, showing a good balance between Volmer and Heyrovsky processes. The Fe&FeP@gl‐C‐15 catalyst shows excellent hydrogen evolution performance in 0.5 m H2SO4, driving a current density of 10 mA cm−2 at an overpotential of 92 mV. Notably, the Fe&FeP@gl‐C‐15 catalyst outperforms a 20 wt% Pt/C catalyst, with a smaller overpotential required to drive a higher current density above 375 mA cm−2.
Funder
Jiangsu Provincial Key Research and Development Program