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Updated: Jun 30, 2025
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Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
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Stable and Highly Active Single Atom Configurations for Photocatalytic H2 Generation
Yue Wang1, Nikita Denisov1, Shanshan Qin1
1Department of Materials Science and Engineering, Chair for Surface Science and Corrosion (WW4-LKO), Friedrich-Alexander-Universität Erlangen-Nürnberg, Martensstraße 7, 91058, Erlangen, Germany.
Advanced Materials (Deerfield Beach, Fla.)
|March 23, 2024
Summary
Platinum single atoms (SAs) boost photocatalytic hydrogen production but tend to clump. Annealing in Ar-H2 stabilizes these SAs, forming rafts that enhance stability and efficiency.
Area of Science:
- Materials Science
- Catalysis
- Nanotechnology
Background:
- Single atoms (SAs), particularly platinum (Pt) SAs, are highly efficient co-catalysts for photocatalytic hydrogen (H2) generation.
- A significant challenge is the light-induced agglomeration of SAs into less active nanoparticles, reducing catalytic performance.
Purpose of the Study:
- To investigate the stability and reactivity of Pt SAs on TiO2 surfaces.
- To develop strategies for preventing SA agglomeration during photocatalysis.
Main Methods:
- Post-deposition annealing treatments of Pt SAs on TiO2 in different atmospheres (air, Ar, Ar-H2) at various temperatures.
- Characterization of SA stability and catalytic performance for H2 production.
Main Results:
- Annealing in an Ar-H2 atmosphere optimally stabilizes Pt SA configurations.
- Stable 2D rafts of assembled SAs (0.5-1 nm diameter) were formed, resisting light-induced agglomeration.
- These stabilized SA rafts demonstrated significantly enhanced H2 production efficiency.
Conclusions:
- Annealing in Ar-H2 provides a promising approach to stabilize Pt SAs on TiO2.
- This method overcomes the critical challenge of SA agglomeration, maintaining high reactivity for photocatalytic H2 generation.
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