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Updated: Jan 14, 2026

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications
Published on: July 25, 2025
Crystallinity-dependent structural evolution of CoS2 catalysts for enhanced oxygen evolution reaction.
Nan Zhang1,2, Yang Hu3, Zhuang Zhang1,2
1State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, China.
Controlling crystallinity in transition metal sulfides (TMSs) is key for stable water oxidation catalysts. Lower crystallinity in cobalt disulfide (CoS2) enhances structural stability and oxygen evolution reaction (OER) performance.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Transition metal sulfides (TMSs) show promise as water oxidation catalysts.
- Structural instability during the oxygen evolution reaction (OER) limits their application.
- The role of crystallinity in TMS structural evolution and OER performance is unclear.
Purpose of the Study:
- To investigate the structural evolution of cobalt disulfide (CoS2) catalysts with varying crystallinities.
- To understand how crystallinity influences OER performance.
- To elucidate the mechanisms behind structural changes during catalysis.
Main Methods:
- In-situ characterization techniques.
- Density functional theory (DFT) calculations.
- Synthesis of CoS2 catalysts with controlled crystallinity.
Main Results:
- Lower crystallinity promotes rapid surface sulfur-oxygen exchange and metal site activation.
- This leads to the formation of sulfur-stabilized oxyhydroxide, enhancing OER performance.
- Moderate crystallinity results in self-corrosion and structural collapse, causing deactivation.
Conclusions:
- Crystallinity control is a viable strategy for optimizing TMS catalysts for water oxidation.
- Tailoring electronic states and catalytic behavior through crystallinity is crucial for improved OER.
- Understanding structural evolution mechanisms is vital for designing stable and efficient water oxidation catalysts.
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