Mo-doping and construction of the heterostructure between NiFe LDH and NiSx co-trigger the activity enhancement for overall water splitting

Wendi Peng; Wenting Zhang; Yanli Lu; Wanping Li; Jiao He; Dan Zhou; Wei Hu; Xinxin Zhong

doi:10.1016/j.jcis.2024.03.062

Mo-doping and construction of the heterostructure between NiFe LDH and NiS_x co-trigger the activity enhancement for overall water splitting

J Colloid Interface Sci. 2024 Jun 15:664:980-991. doi: 10.1016/j.jcis.2024.03.062. Epub 2024 Mar 11.

Authors

Wendi Peng¹, Wenting Zhang¹, Yanli Lu¹, Wanping Li¹, Jiao He¹, Dan Zhou¹, Wei Hu², Xinxin Zhong³

Affiliations

¹ Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei Key Laboratory for Precision Synthesis of Small Molecule Pharmaceuticals, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China.
² Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei Key Laboratory for Precision Synthesis of Small Molecule Pharmaceuticals, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China. Electronic address: huwei76@hubu.edu.cn.
³ Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Hubei Key Laboratory for Precision Synthesis of Small Molecule Pharmaceuticals, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, PR China. Electronic address: xxzhong@hubu.edu.cn.

PMID: 38508033
DOI: 10.1016/j.jcis.2024.03.062

Abstract

To reduce the preparation cost of high-purity hydrogen, it is necessary to search suitable non-precious metal catalysts with high activity and robust stability. Herein, two means (heteroatom-doping and the heterostructure construction) were adopted together to improve the dual-function activity of NiFe LDH which was widely used in water electrolysis. Mo doped NiFe LDH nanoflowers were firstly generated by hydrothermal reaction, and then NiS_x was modified on the petals via electrodeposition. Finally, the obtained NF/Mo-NiFe LDH/NiS_x with large electrochemical active area exhibits the expected electrochemical performance with the overpotential at 100 mA cm^-2 of 169 and 249 mV for hydrogen evolution (HER) and oxygen evolution reaction (OER) respectively. Assembling NF/Mo-NiFe LDH/NiS_x into a two-electrode device for the integral water electrolysis, it just requires a cell voltage of 1.69 V to drive a current density of 100 mA cm^-2, and keeps stable after 50-hour continuous operation in 1.0 M KOH. Mo-doping not only regulates the electronic structure of the transition metals and reduces the energy barrier of HER intermediates, but also facilitates the generation of reactive sites for OER. Meanwhile, the construction of heterointerface ensures the synergism between NiS_x and Mo-NiFe LDH and accelerates the electron transfer across interfaces, thus enhancing the bifunctional performance.

Keywords: Heterointerface; Hydrogen evolution reaction; Oxygen evolution reaction; Transition metal layered double hydroxides; Transition metal sulphides; Water splitting.