Site-selective and real-time observation of bimolecular electron transfer during photocatalytic water splitting

2019/11/04 by Alexander Britz, Britz, Alexander, Sergey I. Bokarev +29
Chemical Engineering · Energy · #Ammonia Synthesis and Nitrogen Reduction #CO2 Reduction Techniques and Catalysts #Chemical Physics (physics.chem-ph) #Electrocatalysts for Energy Conversion #FOS: Physical sciences

paper · pdf · doi:10.48550/arxiv.1911.01254

openalex publication_date 2019/11/04 · openalex created_date 2019/11/22 · openalex updated_date 2026/07/28

Abstract

Time-resolved X-ray absorption spectroscopy has been utilized to monitor the bimolecular electron transfer in a photocatalytic water splitting system for the first time. This has been possible by uniting the local probe and element specific character of X-ray transitions with insights from high-level ab initio calculations. The specific target has been a heteroleptic [Ir^{\rm III}(ppy)₂(bpy)]⁺ photosensitizer, in combination with triethylamine as a sacrificial reductant and Fe₃(CO)₁₂ as a water reduction catalyst. The relevant molecular transitions have been characterized via high-resolution Ir L-edge X-ray absorption spectroscopy on the picosecond time scale. The present findings enhance our understanding of functionally relevant bimolecular electron transfer reactions and thus will pave the road to rational optimization of photocatalytic performance.

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