Rapidly reconstructing the active surface of cobalt-based perovskites for alkaline seawater splitting

Ruigan Hu; Mengyuan Zhao; He Miao; Fuyue Liu; Jiaqun Zou; Chunfei Zhang; Qin Wang; Ziqi Tian; Qiuju Zhang; Jinliang Yuan

doi:10.1039/d2nr01516a

Rapidly reconstructing the active surface of cobalt-based perovskites for alkaline seawater splitting

Nanoscale. 2022 Jul 21;14(28):10118-10124. doi: 10.1039/d2nr01516a.

Authors

Ruigan Hu¹, Mengyuan Zhao², He Miao¹, Fuyue Liu¹, Jiaqun Zou¹, Chunfei Zhang¹, Qin Wang³, Ziqi Tian², Qiuju Zhang², Jinliang Yuan¹

Affiliations

¹ Faculty of Maritime and Transportation, Ningbo University, Ningbo 315211, PR China. miaohe@nbu.edu.cn.
² Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315211, PR China. zhangqj@nimte.ac.cn.
³ Department of Microelectronic Science and Engineering, Faculty of Science, Ningbo University, Ningbo 315211, PR China.

PMID: 35792617
DOI: 10.1039/d2nr01516a

Abstract

As a potential oxygen evolution reaction (OER) catalyst, Co-based perovskites have received intensive attention. However, Sr readily accumulates on their surface, and makes them inert toward the OER. Herein, we propose a simple but versatile electrochemical reduction method to reconstruct the active surface of Co-based perovskites within a few seconds. By this method, Sr rapidly precipitates from Co-based perovskites, accompanied by the introduction of Sr and oxygen vacancies. After reconstruction, the electrochemical active surface areas of Co-based perovskites greatly increase, and the OER overpotential of the optimized SrNb_0.1Co_0.7Fe_0.2O_3-δ (ER-SNCF-20s) reaches 278 mV at 10 mA cm^-2. This can be explained by the decrease of overpotentials at the rate-determining step. Using ER-SNCF-20s, the splitting voltage of alkaline natural seawater can reach 1.56 V at 10 mA cm^-2, and remains steady for 300 h. This effort offers a feasible method for reconstructing the active surface of Co-based perovskites.