Toward a General Understanding of Exciton Self-Trapping in Metal Halide Perovskites
- 22 October 2021
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry Letters
- Vol. 12 (43), 10472-10478
- https://doi.org/10.1021/acs.jpclett.1c02291
Abstract
Self-trapped excitons (STEs) have recently been observed in several metal halide perovskites (MHPs), especially in low-dimensional ones. Despite studies that have shown that factors like dopant, chemical composition, lattice distortion, and structural and electronic dimensionality may all affect the self-trapping of excitons, a general understanding of their mechanism of formation in MHPs is lacking. Here, we study the intrinsic and defect-induced self-trapping of excitons in three-, two-, and one-dimensional MHPs. We find that whether the free excitons could be trapped is simply determined by the competition of the energy-gap decrease and deformation-energy increase along with the lattice distortion. Both introducing halogen defects into the lattice and decreasing the dimensionality can tip the balance between them and thus facilitate the self-trapping of free excitons. This general picture of the mechanism of formation of STEs provides important insights into the design and development of high-performance white-light devices and solar cells with MHPs.Funding Information
- National Natural Science Foundation of China (11634001, 11974105)
- National Basic Research Programs of China (2016YFA0300901)
This publication has 36 references indexed in Scilit:
- Energy transport and scintillation of cerium-doped elpasolite CsLiYCl: Hybrid density functional calculationsPhysical Review B, 2012
- QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materialsJournal of Physics: Condensed Matter, 2009
- Erratum: “Hybrid functionals based on a screened Coulomb potential” [J. Chem. Phys. 118, 8207 (2003)]The Journal of Chemical Physics, 2006
- Electronic and Excitonic Structures of Inorganic–Organic Perovskite-Type Quantum-Well Crystal (C4H9NH3)2PbBr4Japanese Journal of Applied Physics, 2005
- Potential-energy surfaces for excited states in extended systemsThe Journal of Chemical Physics, 2004
- Density-functional theory beyond the Hohenberg-Kohn theoremPhysical Review A, 1999
- Atoms, molecules, solids, and surfaces: Applications of the generalized gradient approximation for exchange and correlationPhysical Review B, 1992
- The self-trapped excitonJournal of Physics and Chemistry of Solids, 1990
- Transition temperature of strong-coupled superconductors reanalyzedPhysical Review B, 1975
- Neutron Spectroscopy of SuperconductorsPhysical Review B, 1972