Computational Investigation of Charge Localization and Structural Dynamics in Halide Perovskites
Licentiatavhandling, 2025

Halide perovskites have gained significant interest due to their remarkable optoelectronic properties and diverse applications. However, most of these applications involve lead-based halide perovskites which suffer from critical challenges related to lead toxicity and long-term stability. In order to counter these challenges various strategies have been explored, including encapsulation, surface passivation, compositional engineering, and alternative synthesis techniques. One of the promising approaches is the development of lead-free halide perovskites. In this licentiate thesis, a computational study is conducted on these materials, using advanced Density Functional Theory calculations and Molecular Dynamics simulations employing neuroevolution potentials. The structural properties, with a particular focus on octahedral tilting and phase transitions are explored. Furthermore, charge localizations in the form of polarons in Cs2AgBiBr6 and CsGeX3 (X=Cl,Br,I) are investigated. Additionally, the formation of self-trapped excitons in Cs2AgBiBr6 is  examined. These self-trapped states play an important role in the material optical properties reported in several experimental reports. Overall, the results in this work provide valuable insights on the structural and electronic properties of lead-free halide perovskites.

halide double perovskite

density functional theory

halide per- ovskites

lead-free

self-trapped exciton

polaron

molecular dynamics

PJ-salen, byggnadFysik Origo, Chalmers
Opponent: Maning Liu, Lund University, Sweden

Författare

Mehmet Baskurt

Chalmers, Fysik, Kondenserad materie- och materialteori

Charge Localization in Cs<inf>2</inf>AgBiBr<inf>6</inf> Double Perovskite: Small Polarons and Self-Trapped Excitons

Journal of Physical Chemistry C,;Vol. 127(2023)p. 23966-23972

Artikel i vetenskaplig tidskrift

Baskurt, M., Karlsson, M., Fransson, E., Erhart, P., Wiktor, J. Effects of Lone-Pair Electrons on the Octahedral Tilting in Halide Dou- ble Perovskites

Baskurt, M., Wiktor, J. Exploring the Polaron Landscape in Lead-Free Germanium Halide Per- ovskites: CsGeCl3 , CsGeBr3 , and CsGeI3

Fasbeteende och elektroniska egenskaper hos halogenid-perovskiter från simulering på atomskala

Vetenskapsrådet (VR) (2020-04935), 2020-12-01 -- 2024-11-30.

Atomistisk design av fotoadsorberande material

Vetenskapsrådet (VR) (2019-03993), 2020-01-01 -- 2023-12-31.

Ämneskategorier (SSIF 2025)

Den kondenserade materiens fysik

Infrastruktur

C3SE (-2020, Chalmers Centre for Computational Science and Engineering)

Styrkeområden

Materialvetenskap

Utgivare

Chalmers

PJ-salen, byggnadFysik Origo, Chalmers

Opponent: Maning Liu, Lund University, Sweden

Mer information

Senast uppdaterat

2025-03-24