Phosphorus-doped Fe7Ss@C nanowires for efficient electrochemical hydrogen and oxygen evolutions: Controlled synthesis and electronic modulation on active sites

• 作者: Thanh-Tung Le Xiao Liu Peijun Xin Qing Wang Chunyan Gao Ye Wu Yong Jiang Zhangjun Hu Shoushuang Huang Zhiwen Chen
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（15）
• 页码范围: 168-175
• 页数: 8页
• 语种: 英文

摘要

Developing low-cost,efficient,and stable non-precious-metal electrocatalysts with controlled crystal structure,morphology and compositions are highly desirable for hydrogen and oxygen evolution reactions.Herein,a series of phosphorus-doped Fe7S8 nanowires integrated within carbon (P-Fe7S8@C) are rationally synthesized via a one-step phosphorization of one-dimensional (1D) Fe-based organicinorganic nanowires.The as-obtained P-Fe7S8@C catalysts with modified electronic configurations present typical porous structure,providing plentiful active sites for rapid reaction kinetics.Density functional calculations demonstrate that the doping Fe7S8 with P can effectively enhance the electron density of Fe7S8 around the Fermi level and weaken the Fe-H bonding,leading to the decrease of adsorption free energy barrier on active sites.As a result,the optimal catalyst of P-Fe7S8-600@C exhibits a relatively low overpotential of 136 mV for hydrogen evolution reaction (HER) to reach the current density of 10 mA/cm2,and a significantly low overpotential of 210 mV for oxygen evolution reaction (OER) at 20mA/cm2 in alkaline media.The work presented here may pave the way to design and synthesis of other prominent Fe-based catalysts for water splitting via electronic regulation.