摘要
Exploring cost-effective and highly-active oxygen evolution reaction(OER)electrocatalysts is a pressing task to propel water electrolysis for green hydrogen production.Herein,we constructed a class of Fe-doped and Senriched Ni_(3)S_(2)nanowires electrocatalysts for optimizing the target intermediates adsorption to decrease the OER overpotentials at various current densities.The optimal Ni_(3)S_(2)-1.4%Fe electrocatalyst possesses the most active sites and exhibits an ultralow overpotential of 190 mV at 10 mA cm^(-2) with an excellent stability of>60 h,exceeding the majority of recently-reported Ni_(3)S_(2)-based electrocatalysts.The trivalence Fe-doping not only reduces the electron density of the Ni center,but also enables the sulfur enrichment on the Ni_(3)S_(2) surface,which greatly improves the intrinsic activity and the number of target intermediates(*OOH).A novel methanol-assisted electrochemical evaluation further reveals that the Ni_(3)S_(2)-1.4%Fe electrocatalyst demonstrates a weaker binding ability to*OH with the rapid generation of*OOH species,and thus gives a lower apparent activation energy compared with the surface sulfur reduced ones.This work provides a new perspective for regulating the adsorption of intermediates through doping strategy.
基金
supported by the National Natural Science Foundation of China(21838003)
the Innovation Program of Shanghai Municipal Education Commission,and the Fundamental Research Funds for the Central Universities(222201718002).
