title: Structural and Thermal Disorder of Solution-Processed CH3NH3PbBr3Hybrid Perovskite Thin Films.
abstract: We extracted the electronic disorder energy of the organic-inorganic lead-halide hybrid perovskite CH3NH3PbBr3from temperature-dependent absorption data. We showed that the disorder at room temperature is ∼30 meV and is due to strong electron-phonon coupling with the longitudinal-optical mode of energy 16 meV. This mode can be attributed to longitudinal-optical phonons of the inorganic PbBr6frame; this conclusion highlights the polaronic nature of electronic excitations in CH3NH3PbBr3. We showed that structural disorder is of the same impact as thermal disorder. A temperature-dependence of the exciton binding energy was observed close to the orthorhombic-to-tetragonal phase-transition temperature.
authors.affiliation: Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH) . Pohang, Gyungbuk 37673, Republic of Korea.
authors.forename: Christoph
authors.identifier: http://orcid.org/0000-0002-9340-9782
authors.initials: C
authors.lastname: Wolf
authors.affiliation: Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH) . Pohang, Gyungbuk 37673, Republic of Korea.|Department of Materials Science and Engineering, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
authors.forename: Joo-Sung
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Materials Science and Engineering, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
authors.forename: Tae-Woo
authors.identifier: http://orcid.org/0000-0002-6449-6725
authors.initials: TW
authors.lastname: Lee
keywords: Urbach energy; disorder; exciton binding energy; hybrid lead-halide perovskite; spectroscopy