Nanostructured amorphous Fe₂₉Co₂₇Ni₂₃Si₉B₁₂ high-entropy-alloy:an efficient electrocatalyst for oxygen evolution reaction

Hongyan Wang¹，Ran Wei¹，Xiumin Li¹，Xuli Ma²，Xiaogang Hao³，Guoqing Guan⁴

1. School of Materials Science and Engineering, Zhengzhou University2. Department of Environmental Science and Engineering, Taiyuan University of Technology3. Department of Chemical Engineering, Taiyuan University of Technology4. Energy Conversion Engineering Laboratory, Institute of Regional Innovation, Hirosaki University

摘 要：Proximal configu ration of dissimilar metal atoms in amorphous high-entropy-alloys（HEAs） always re sult in interatomic d-band ligand effect,dense defect distribution,coordinatively unsaturated sites,high potential energy,and loose atom bonding.Herein,nanostructured amorphous Fe₂₉CO₂₇Ni₂₃Si₉ B₁₂ HEA ribbon is fabricated via a melt spinning method combined with electrochemical corrosion etching process,which is applied as the potential oxygen evolution reaction electrocatalyst.It is found that there are micro/nano pits on the surface of etched amorphous Fe₂₉CO₂₇Ni₂₃Si₉ B₁₂ ribbons.Various elements of HEAs bond with each other to form a highly disordered configu ration,which could result in an optimized bonding energy and enhanced intrinsic catalytic activity.The electrocatalysis activity measurements indicate that the amorphous HEA endows a much higher activity than the crystalline one,which is further improved by the electrochemical etching treatment.Especially,the HEA ribbon etched for 3 h requires a low overpotential of 230 mV to afford 10 mA cm^-2 current density.In addition,density functional theory calculations demonstrate that the amorphous structure can weaken the interaction between the surface of Fe₂₉CO₂₇Ni₂₃Si₉ B₁₂ alloy and the intermediates,leading to an optimized adsorption Gibbs free energy.

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