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Published on: May 27, 2020
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Photoinduced Charge Accumulation in Molecular Systems
Annabell G Bonn1, Oliver S Wenger2
1Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland.
Chimia
|October 7, 2017
Summary
Researchers are developing molecular systems to capture light energy for chemical fuel production. Key systems include metal complexes and organic units, with some avoiding sacrificial electron donors for efficient charge accumulation.
Area of Science:
- * Molecular photochemistry
- * Renewable energy research
- * Catalysis
Background:
- * Fuel-forming reactions (e.g., CO2 reduction, water splitting) require multiple redox equivalents.
- * Light-driven production of solar fuels necessitates mastering photoinduced charge accumulation.
- * Molecular components are crucial for collecting electrons or holes.
Purpose of the Study:
- * To review key molecular systems for photoinduced charge accumulation.
- * To highlight advances in solar fuel research.
- * To discuss strategies for efficient redox equivalent accumulation.
Main Methods:
- * Exploration of molecular systems, including metal complexes and organic moieties.
- * Investigation of charge accumulation mechanisms.
- * Analysis of systems with and without sacrificial electron donors.
Main Results:
- * Several molecular systems capable of charge accumulation were identified.
- * Examples include trinuclear Ru-Rh-Ru complexes, Ir-sensitized polyoxotungstates, and organic units (perylenebis(dicarboximide), quinones, oligotriarylamines).
- * Some systems achieve charge accumulation without sacrificial electron donors.
Conclusions:
- * Molecular systems are vital for efficient solar fuel production.
- * Diverse molecular architectures can facilitate photoinduced charge accumulation.
- * Eliminating sacrificial donors represents a significant advancement.
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