Article Title

Room-temperature ligancy engineering of perovskite electrocatalyst for enhanced electrochemical water oxidation

Authors

Junchi Wu, Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), and CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 230026, China
Yuqiao Guo, Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), and CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 230026, China
Haifeng Liu, Analytical and Testing Center, Southwest University of Science and Technology, Mianyang 621010, China
Jiyin Zhao, Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), and CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 230026, China
Haodong Zhou, Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), and CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 230026, China
Wangsheng Chu, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China
Changzheng Wu, Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), and CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 230026, China

Keywords

perovskite oxides, ligancy engineering, oxygen evolution reaction, electrocatalysts

Abstract

Perovskite oxides are significant candidates to develop electrochemical catalysts for water oxidation in consideration of their high catalysis capacity, low costing and excellent stability. Rational design of coordination structure and overcoming poor electronic transport are regarded as critical factors for outstanding perovskite-based oxygen evolution reaction (OER) catalysts. Herein, we report a mild chemical oxidation method to realize ligancy engineering from strongly-correlated brownmillerite Sr2Co2O5 to perovskite phase Sr2Co2O5.5, along with abundant oxygen vacancies formation and greatly boosted electric conductivity, which helps to form the active species of Co hydroxide/oxide on the surface of catalysts. The coupling effect of catalytic kinetics and unimpeded electronic movement brings high OER activities in Sr2Co2O5.5 with a low onset potential and a small Tafel slope. Our work not only displays in-depth understanding into the relationship among catalysis performance and multiple physical degrees of freedom, but also paves a new path to develop high-efficient electrochemical catalysts.

Graphical Abstract

DOI

https://doi.org/10.1007/s12274-019-2409-5

Publisher

Tsinghua University Press

Recommended Citation

Junchi Wu,Yuqiao Guo,Haifeng Liu,Jiyin Zhao,Haodong Zhou,Wangsheng Chu,Changzheng Wu, Room-temperature ligancy engineering of perovskite electrocatalyst for enhanced electrochemical water oxidation. NanoRes.2019, 12(9): 2296–2301