Ultrafast Dynamics of Electronic and Structural Modifications Induced by Photoexcitation in Cerium Oxide
Abstract Pump‐probe spectroscopies utilizing X‐ray free‐electron lasers offer element‐specific insights into the processes occurring in photocatalysts following photoexcitation, which are essential for the rational optimization of the efficiency of these materials. This study examines the dynamic evolution of the electronic and atomic structure in stoichiometric cerium oxide films following photoexcitation, employing ultrafast pump‐probe X‐ray absorption spectroscopy (XAS) at the Ce L 3 edge in both the near‐edge and extended energy ranges using an X‐ray free electron laser. The results reveal a rapid relaxation pathway occurring within the first few hundred femtoseconds, followed by the formation of an excited state with a lifetime on the order of hundreds of picoseconds. The analysis of pump‐probe XAS in the extended energy range identifies a structural distortion consistent with the formation of a photoinduced small polaron state. The observed time correlation between the photoinduced electronic and structural changes further reinforces the hypothesis of photoinduced polaron formation. Constrained density functional theory simulations offer insights into the electronic modifications and structural distortions in the photoexcited material. The consequences of the observed processes on material functionality are discussed.
Authors
- Samuele Pelatti
- Patrick O’Keeffe (ORCID: https://orcid.org/0000-0002-8676-4436)
- Daniele Catone (ORCID: https://orcid.org/0000-0002-7649-2756)
- Eleonora Spurio (ORCID: https://orcid.org/0000-0002-0708-0299)
- A. di Bona (ORCID: https://orcid.org/0000-0003-3923-4210)
- Dmitry Khakhulin (ORCID: https://orcid.org/0000-0002-4453-1204)
- Stefano Turchini (ORCID: https://orcid.org/0000-0003-0122-0614)
- Daniele Varsano (ORCID: https://orcid.org/0000-0001-7675-7374)
- Doriana Vinci (ORCID: https://orcid.org/0000-0001-8841-6534)
- Yifeng Jiang (ORCID: https://orcid.org/0000-0003-0685-0498)
- P. Luches (ORCID: https://orcid.org/0000-0003-1310-5357)
- Peter Zalden (ORCID: https://orcid.org/0000-0002-8530-0576)
- Giuseppe Ammirati (ORCID: https://orcid.org/0000-0002-4185-6222)
- Stefania Benedetti (ORCID: https://orcid.org/0000-0002-2683-4818)
- F. Boscherini (ORCID: https://orcid.org/0000-0002-9703-3903)
- Sergio D’Addato (ORCID: https://orcid.org/0000-0002-2002-2069)
- Mykola Biednov (ORCID: https://orcid.org/0000-0003-2219-155X)
- Frederico A. Lima (ORCID: https://orcid.org/0000-0001-8106-2892)
- Fulvio Paleari (ORCID: https://orcid.org/0000-0001-8038-8575)
- Yohei Uemura (ORCID: https://orcid.org/0000-0003-3164-7168)
- Christopher J. Milne (ORCID: https://orcid.org/0000-0003-4714-9139)
- Hao Wang (ORCID: https://orcid.org/0000-0001-5892-3412)
- Xin‐Chao Huang (ORCID: https://orcid.org/0000-0002-9140-6369)
Institutions
- University of Modena and Reggio Emilia (IT)
- AREA Science Park (IT)
- Istituto Nanoscienze (IT)
- Istituto Officina dei Materiali (IT)
- Institute of Structure of Matter (IT)
- European X-Ray Free-Electron Laser (DE)
Publication Details
- Journal
- Advanced Electronic Materials
- Published
- 2025-09-19
- DOI
- https://doi.org/10.1002/aelm.202500429
- Primary Topic
- Catalytic Processes in Materials Science
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- European Commission
- Ministero degli Affari Esteri e della Cooperazione Internazionale