Duplex Interpenetrating-Phase FeNiZn and FeNi3 Heterostructure with Low-Gibbs Free Energy Interface Coupling for Highly Efficient Overall Water Splitting

Qiuxia Zhou; Caixia Xu; Jiagang Hou; Wenqing Ma; Tianzhen Jian; Shishen Yan; Hong Liu

doi:10.1007/s40820-023-01066-w

Duplex Interpenetrating-Phase FeNiZn and FeNi₃ Heterostructure with Low-Gibbs Free Energy Interface Coupling for Highly Efficient Overall Water Splitting

Nanomicro Lett. 2023 Apr 10;15(1):95. doi: 10.1007/s40820-023-01066-w.

Authors

Qiuxia Zhou^{1

2}, Caixia Xu³, Jiagang Hou⁴, Wenqing Ma¹, Tianzhen Jian¹, Shishen Yan¹, Hong Liu^{5

6}

Affiliations

¹ Institute for Advanced Interdisciplinary Research (iAIR), Spintronics Institute, Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, People's Republic of China.
² School of Medical Information and Engineering, Southwest Medical University, Luzhou, 646000, People's Republic of China.
³ Institute for Advanced Interdisciplinary Research (iAIR), Spintronics Institute, Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, People's Republic of China. chm_xucx@ujn.edu.cn.
⁴ Kyiv College at Qilu University of Technology, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250353, People's Republic of China.
⁵ Institute for Advanced Interdisciplinary Research (iAIR), Spintronics Institute, Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, People's Republic of China. ifc_liuh@ujn.edu.cn.
⁶ State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, People's Republic of China. ifc_liuh@ujn.edu.cn.

Abstract

The sluggish kinetics of both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) generate the large overpotential in water electrolysis and thus high-cost hydrogen production. Here, multidimensional nanoporous interpenetrating-phase FeNiZn alloy and FeNi₃ intermetallic heterostructure is in situ constructed on NiFe foam (FeNiZn/FeNi₃@NiFe) by dealloying protocol. Coupling with the eminent synergism among specific constituents and the highly efficient mass transport from integrated porous backbone, FeNiZn/FeNi₃@NiFe depicts exceptional bifunctional activities for water splitting with extremely low overpotentials toward OER and HER (η₁₀₀₀ = 367/245 mV) as well as the robust durability during the 400 h testing in alkaline solution. The as-built water electrolyzer with FeNiZn/FeNi₃@NiFe as both anode and cathode exhibits record-high performances for sustainable hydrogen output in terms of much lower cell voltage of 1.759 and 1.919 V to deliver the current density of 500 and 1000 mA cm^-2 as well long working lives. Density functional theory calculations disclose that the interface interaction between FeNiZn alloy and FeNi₃ intermetallic generates the modulated electron structure state and optimized intermediate chemisorption, thus diminishing the energy barriers for hydrogen production in water splitting. With the merits of fine performances, scalable fabrication, and low cost, FeNiZn/FeNi₃@NiFe holds prospective application potential as the bifunctional electrocatalyst for water splitting.

Keywords: Bifunctional electrocatalyst; Dealloying; Heterostructure; Interface effect; Overall water splitting.