Phosphate-modified cobalt silicate hydroxide with improved oxygen evolution reaction

Chongtao Ding; Yao Yu; Yu Wang; Yang Mu; Xueying Dong; Changgong Meng; Chi Huang; Yifu Zhang

doi:10.1016/j.jcis.2023.06.007

Phosphate-modified cobalt silicate hydroxide with improved oxygen evolution reaction

J Colloid Interface Sci. 2023 Oct 15:648:251-258. doi: 10.1016/j.jcis.2023.06.007. Epub 2023 Jun 3.

Authors

Chongtao Ding¹, Yao Yu², Yu Wang¹, Yang Mu¹, Xueying Dong¹, Changgong Meng³, Chi Huang⁴, Yifu Zhang⁵

Affiliations

¹ State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
² College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
³ State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China; College of Environmental and Chemical Engineering, Dalian University, Dalian 116622, China.
⁴ College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China. Electronic address: chihuang@whu.edu.cn.
⁵ State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China. Electronic address: yfzhang@dlut.edu.cn.

PMID: 37301149
DOI: 10.1016/j.jcis.2023.06.007

Abstract

Oxygen Evolution Reaction (OER) has gained significant attention due to its crucial role in renewable energy systems. The quest for efficient and low-cost OER catalysts remains a challenge of significant interest and importance. In this work, phosphate-incorporated cobalt silicate hydroxide (denoted as CoSi-P) is reported as a potential electrocatalyst for OER. The researchers first synthesized hollow spheres of cobalt silicate hydroxide Co₃(Si₂O₅)₂(OH)₂ (denoted as CoSi) using SiO₂ spheres as a template through a facile hydrothermal method. Phosphate (PO₄^3-) was then introduced to layered CoSi, leading to the reconstruction of the hollow spheres into sheet-like architectures. As expected, the resulting CoSi-P electrocatalyst demonstrated low overpotential (309 mV at 10 mA·cm^-2), large electrochemical active surface area (ECSA), and low Tafel slope. These parameters outperform CoSi hollow spheres and cobaltous phosphate (denoted as CoPO). Moreover, the catalytic performance achieved at 10 mA cm^-2 is comparable or even better than that of most transition metal silicates/oxides/hydroxides. The findings indicate that the incorporation of phosphate into the structure of CoSi can enhance its OER performance. This study not only provides a non-noble metal catalyst CoSi-P but also demonstrates that the incorporation of phosphates into transition metal silicates (TMSs) offers a promising strategy for the design of robust, high-efficiency, and low-cost OER catalysts.

Keywords: Co(3)(Si(2)O(5))(2)(OH)(2) hollow spheres; Electrocatalyst; Oxygen evolution reaction; Phosphorization; Surface decoration.