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Updated: Jun 1, 2026
10:21
Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
Light-induced water oxidation at silicon electrodes functionalized with a cobalt oxygen-evolving catalyst
Joep J H Pijpers1, Mark T Winkler, Yogesh Surendranath
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA.
Summary
Researchers developed a stable, photo-assisted anode using a silicon solar cell and cobalt-based water-splitting catalyst (Co-Pi). This innovation advances direct solar-to-fuel energy conversion by efficiently splitting water into oxygen at neutral pH.
Area of Science:
- Materials Science
- Electrochemistry
- Renewable Energy
Background:
- Direct solar-to-fuel technologies aim to convert solar energy into storable fuels.
- Water splitting is a key process for producing hydrogen fuel.
- Developing efficient and stable catalysts for water splitting at neutral pH is challenging.
Purpose of the Study:
- To create a robust, monolithic photo-assisted anode for water splitting.
- To utilize a silicon solar cell integrated with a cobalt-based catalyst (Co-Pi).
- To achieve efficient oxygen evolution at neutral pH.
Main Methods:
- Integration of a np-Si junction solar cell with a cobalt-based water-splitting catalyst (Co-Pi).
- Deposition of Co-Pi catalyst on an Indium Tin Oxide (ITO)-passivated p-side of the silicon junction.
- Photo-assisted water splitting to O(2) under neutral pH conditions.
Main Results:
- A stable, monolithic photo-assisted anode was successfully fabricated.
- The integrated system efficiently drives water splitting to O(2) at neutral pH.
- Enhanced anode stability was observed at neutral pH compared to alkaline conditions.
Conclusions:
- The developed construct represents a significant advancement in direct solar-to-fuel energy conversion.
- This approach offers a pathway towards inexpensive and stable solar fuel technologies.
- The Co-Pi catalyst on silicon shows promise for practical photo-electrochemical water splitting.
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