S-modified NiFe-phosphate hierarchical hollow microspheres for efficient industrial-level seawater electrolysis

Shiwei Song; Yanhui Wang; Xueqing Tian; Fanjia Sun; Xiaoxu Liu; Yungang Yuan; Wei Li; Jianbing Zang

doi:10.1016/j.jcis.2022.11.113

S-modified NiFe-phosphate hierarchical hollow microspheres for efficient industrial-level seawater electrolysis

J Colloid Interface Sci. 2023 Mar:633:668-678. doi: 10.1016/j.jcis.2022.11.113. Epub 2022 Nov 28.

Authors

Shiwei Song¹, Yanhui Wang¹, Xueqing Tian¹, Fanjia Sun¹, Xiaoxu Liu², Yungang Yuan¹, Wei Li¹, Jianbing Zang³

Affiliations

¹ State Key Laboratory of Metastable Materials Science and Technology, School of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004, PR China.
² Department of Physics, Hebei Normal University of Science and Technology, Qinhuangdao 066004, PR China.
³ State Key Laboratory of Metastable Materials Science and Technology, School of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004, PR China. Electronic address: diamondzjb@163.com.

PMID: 36473357
DOI: 10.1016/j.jcis.2022.11.113

Abstract

For sustained hydrogen generation from seawater electrolysis, an efficient and specialized catalyst must be designed to cope with the slow anode reaction and chloride ions (Cl^-) corrosion. In this work, an S-modified NiFe-phosphate with hierarchical and hollow microspheres was grown on the NiFe foam skeleton (S-NiFe-Pi/NFF), acting as a bifunctional catalyst to enable industrial-scale seawater electrolysis. The introduction of S distorted the lattice of NiFe-phosphate and regulated the local electronic environment around Ni/Fe active metal, both of which enhanced the electrocatalytic activity. Additionally, the existence of phosphate groups repelled Cl^- on the surface and enhanced corrosion resistance, enabling stable long-term operation in seawater. The double-electrode electrolyzer composed of the hollow-structured S-NiFe-Pi/NFF as both cathode and anode exhibited a potential of 1.68 V at 100 mA cm^-2 for seawater electrolysis. Particularly, to achieve industrial requirements of 500 mA cm^-2, it only required a low cell voltage of 1.8 V and demonstrated a consistent response over 100 h, which outperformed the pair of Pt/C || IrO₂. This study provides a feasible idea for the preparation of electrocatalysts that are with both highly activity and corrosion resistance, which is crucial for the implementation of industrial-scale seawater electrolysis.

Keywords: Corrosion resistance; Hollow microspheres; S-modified NiFe-phosphate; Seawater electrolysis.