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Switching Urea Oxidation Reaction Pathways by Regulating Multi-Component Sites on Chlorine-Doped Nickel-Cobalt
Yuan Rui1, Yunxia Liu2, Fuqi Zheng1
1School of Physics and Information Technology, Shaanxi Normal University, Xi'an, Shaanxi, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|July 27, 2026
Summary
Researchers switched urea oxidation reaction (UOR) pathways using nickel-cobalt hydroxides with tunable oxygen vacancies. This discovery enhances hydrogen production efficiency and reveals key structure-pathway relationships in electrocatalysis.
Area of Science:
- Electrochemistry
- Materials Science
- Catalysis
Background:
- Urea oxidation reaction (UOR) is a promising alternative to oxygen evolution reaction for hydrogen production.
- Two main UOR pathways exist: a direct six-electron process and a two-stage pathway.
- Controlling UOR pathways is crucial for optimizing hydrogen generation.
Purpose of the Study:
- To demonstrate pathway switching in UOR by manipulating oxygen vacancies.
- To elucidate the relationship between catalyst structure and UOR pathways.
- To develop highly efficient electrocatalysts for UOR.
Main Methods:
- Synthesized nickel-cobalt hydroxides with controlled oxygen vacancy concentrations.
- Employed extensive experimental characterizations.
- Utilized density functional theory (DFT) calculations.
Main Results:
- Successfully switched UOR pathways by tuning oxygen vacancies.
- Identified "multi-component active sites" and their role in UOR.
- Achieved record performance with chlorine-substituted nickel-cobalt hydroxides (NiCoClOH) for Ni3+ active sites.
Conclusions:
- Demonstrated a novel method for controlling UOR pathways.
- Provided fundamental insights into the structure-pathway relationship in UOR.
- Developed highly efficient electrocatalysts for sustainable hydrogen production.
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