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Photoinduced biphasic hydrogen evolution: decamethylosmocene as a light-driven electron donor
Peiyu Ge1, Astrid J Olaya, Micheál D Scanlon
1Laboratoire d'Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne, Station 6, 1015 Lausanne, Switzerland.
Summary
Light-induced hydrogen evolution is achieved using decamethylosmocene, a weak electron donor. This process efficiently forms decamethylosmocenium hydride under biphasic conditions, outperforming single-phase reactions.
Area of Science:
- Photochemistry
- Organometallic Chemistry
- Catalysis
Background:
- Decamethylosmocene acts as a weak electron donor.
- Excited states can drive chemical reactions.
- Hydrogen evolution is a key area in sustainable energy research.
Purpose of the Study:
- To investigate the mechanism and kinetics of light-driven hydrogen evolution.
- To understand the role of biphasic conditions in this process.
- To compare the efficiency of hydride formation in different reaction media.
Main Methods:
- Gas chromatography
- Cyclic voltammetry
- UV/Vis spectroscopy
- (1)H NMR spectroscopy
Main Results:
- Excited decamethylosmocene reduces solubilized protons under biphasic conditions.
- Decamethylosmocenium hydride forms rapidly and independently of light.
- Biphasic conditions yield higher hydride formation efficiency (90%) compared to single-phase (20%).
- Decamethylosmocene exhibits greater proton affinity than decamethylferrocene or osmocene.
Conclusions:
- Decamethylosmocene is an effective photo-induced hydrogen evolution agent.
- Biphasic conditions significantly enhance hydride formation efficiency.
- Proton affinity plays a crucial role in the observed reactivity.
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