Preparation of hierarchical hollow CoFe Prussian blue analogues and its heat-treatment derivatives for the electrocatalyst of oxygen evolution reaction

Ying Wei; Mingbo Zheng; Wei Zhu; Yi Zhang; Wenhui Hu; Huan Pang

doi:10.1016/j.jcis.2022.11.014

Preparation of hierarchical hollow CoFe Prussian blue analogues and its heat-treatment derivatives for the electrocatalyst of oxygen evolution reaction

J Colloid Interface Sci. 2023 Feb;631(Pt B):8-16. doi: 10.1016/j.jcis.2022.11.014. Epub 2022 Nov 8.

Authors

Ying Wei¹, Mingbo Zheng², Wei Zhu¹, Yi Zhang¹, Wenhui Hu³, Huan Pang⁴

Affiliations

¹ School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, Jiangsu, PR China.
² School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, Jiangsu, PR China; College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, Jiangsu, PR China. Electronic address: zhengmingbo@nuaa.edu.cn.
³ School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, Jiangsu, PR China; Interdisciplinary Materials Research Center, Institute for Advanced Study, Chengdu University, Chengdu 610106, PR China.
⁴ School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, Jiangsu, PR China. Electronic address: panghuan@yzu.edu.cn.

PMID: 36379117
DOI: 10.1016/j.jcis.2022.11.014

Abstract

The microstructure of materials importantly affects their performance. As electrocatalyst materials, the performance of hollow-structure materials is usually better than that of solid materials because of the larger specific surface area, lower density, and more exposed active sites of hollow structure. Bimetallic catalysts usually exhibit better catalytic activity than monometallic catalysts because of the synergistic effects between different metal elements. Prussian blue and its analogues (PB/PBAs) are ideal precursors for preparing hollow-structure bimetallic catalysts due to their structure and composition characteristics. In this study, ZIF-67 hollow sphere (HS) was used as the template to prepare hierarchical hollow CoFePBA (H-SCP) through anion-exchange method. The oxygen evolution reaction (OER) catalytic performance of H-SCP was further improved by low-temperature heat treatment in N₂ atmosphere. The H-SCP-350 sample, which was obtained at a heat-treatment temperature of 350 ℃, was a bimetallic nanocomposite. Part of H-SCP was converted into metallic cobalt and cobalt-iron alloy during heat treatment. The synergistic effect among the different components effectively improved the electrocatalytic activity of the material. Therefore, H-SCP-350 showed the best OER catalytic performance among all samples. The overpotential was only 291mV at a current density of 10 mA cm^-2 when tested in 1 M KOH electrolyte.

Keywords: Co-based catalysts; Electrocatalyst; Hierarchical hollow structure; Oxygen evolution reaction; Prussian blue analogues.