Theoretical Investigation of Photo-Electro-Catalysis Beyond Proton-Coupled Electron Transfer

• Applicant: Professor Dr. Harald Oberhofer
• Subject Area: Theoretical Chemistry: Molecules, Materials, Surfaces
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 316851445

For the design and optimisation of industrially viable (photo-) electrocatalysts, e.g. for water oxidation, the atomistic understanding and therefore more and more theoretical simulation of individual reaction steps is of vital importance. Based on relatively simple considerations theoretical screening results helped pave the way to find more and more efficient catalysts, yet also pointed out ultimate limits of the efficiency reachable with metallic catalysts. One way to go beyond these is to look to other classes of materials such as oxides, sulfides and nitrides. There, the scaling relations underlying the efficiency limits do not generally hold. On the other hand, many of the assumptions commonly employed in the study of electrochemical surface reactions do not hold either. For example in oxides, possibly charged defects are known to play a key role in the reactivity. Also, in semi-conductors electrochemical reaction steps do not necessarily have to proceed through neutral intermediates via proton-coupled electron transfer (PCET). We propose to develop a simulation protocol, based on solid-state and liquid embedding techniques, tailored to address these two key issues. Due to the embedding, we will be able to study reaction pathways beyond PCET, including charged intermediates and their interplay with charged defects. We will apply this general protocol first to study water splitting on the (defected) prototypical TiO2 (110) surface, unbiased with respect to the reaction pathway.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Karsten Reuter