Superhydrophilic Porous CoOOH Nano-Architecture with Abundant Oxygen Vacancies for Enhanced Urea Electrooxidation at Ampere-Level Current Densities

Authors

Wen-Jing Lv, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.
Xiao-Man Tang, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.
Xue-Tong Wang, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.
Wen-Cai Liu, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.
Jian-Wen Zhu, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.
Guo-Jing Wang, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.Follow
Yuan-Zhi Zhu, Faculty of Chemical Engineering, Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical， Engineering and New Phosphorus Materials， Kunming University of Science and Technology， Kunming 650500, Yunnan, China.Follow

Document Type

Article

Corresponding Author(s)

Guo-Jing Wang(gjwang@kust.edu.cn);
Yuan-Zhi Zhu(yuanzhi_zhu@kust.edu.cn)

Abstract

The conversion of urea-containing wastewater into clean hydrogen energy has gained increasing attention. However, challenges remain, particularly with sluggish catalytic kinetics and limited long-term stability of urea oxidation reaction (UOR). Herein, we report loosely porous CoOOH nano-architecture (CoOOH LPNAs) with hydrophilic surface and abundant oxygen vacancies (O_v) on carbon fiber paper (CFP) by electrochemical reconstruction of the CoP nanoneedles precursor. The resulting three-dimensional electrode exhibits an impressively low potential of 1.38 V at 1000 mA cm⁻² and excellent durability for UOR. Furthermore, in an anion exchange membrane (AEM) electrolyzer, it requires only 1.53 V at 1000 mA cm⁻² for industrial urea-assisted water splitting and operates stably for 100 h without degradation. Experimental and theoretical investigations reveal that rich oxygen vacancies effectively modulate the electronic structure of the CoOOH while creating unique Co₃-triangle sites with Co atoms close together. As a result, the adsorption and desorption processes of reactants and intermediates in UOR are finely tuned, thereby significantly reducing thermodynamic barriers. Additionally, the superhydrophilic self-supported nanoarray structure facilitates rapid gas bubble release, improving the overall efficiency of the reaction and preventing potential catalyst detachment caused by bubble accumulation, thereby improving both catalytic activity and stability at high current densities.

Graphical Abstract

Keywords

CoOOH, electrochemical reconstruction, oxygen vacancies, superhydrophilic surface, urea electrooxidation

DOI

10.61558/2993-074X.3550

Online Date

5-21-2025

Recommended Citation

Wen-Jing Lv, Xiao-Man Tang, Xue-Tong Wang, Wen-Cai Liu, Jian-Wen Zhu, Guojing Wang, Yuanzhi Zhu. Superhydrophilic Porous CoOOH Nano-Architecture with Abundant Oxygen Vacancies for Enhanced Urea Electrooxidation at Ampere-Level Current Densities[J]. Journal of Electrochemistry, doi: 10.61558/2993-074X.3550.