Free Carriers versus Excitons in CH3NH3PbI3 Perovskite Thin Films at Low Temperatures: Charge Transfer from the Orthorhombic Phase to the Tetragonal Phase
We have investigated the dynamic optical properties of CH3NH3PbI3 (MAPbI3) perovskite thin films at low temperatures using time-resolved photoluminescence, optical transient absorption (TA), and THz TA spectroscopy. Optical spectroscopic results indicate that the high-temperature tetragonal phase still remains in the MAPbI3 thin films at low temperatures in addition to the major orthorhombic phase. The fast charge transfer from the orthorhombic phase to the tetragonal phase is likely to suppress the formation of excitons in the orthorhombic phase. Consequently, the near-band-edge optical responses of the photocarriers in both the tetragonal and orthorhombic phases of the MAPbI3 thin films are more accurately described by a free-carrier model, rather than an excitonic model even at low temperatures.
%0 Journal Article
%1 doi:10.1021/acs.jpclett.6b00781
%A Phuong, Le Quang
%A Yamada, Yasuhiro
%A Nagai, Masaya
%A Maruyama, Naoki
%A Wakamiya, Atsushi
%A Kanemitsu, Yoshihiko
%D 2016
%J The Journal of Physical Chemistry Letters
%K charge-transfer perovskite phase
%N 13
%P 2316-2321
%R 10.1021/acs.jpclett.6b00781
%T Free Carriers versus Excitons in CH3NH3PbI3 Perovskite Thin Films at Low Temperatures: Charge Transfer from the Orthorhombic Phase to the Tetragonal Phase
%U http://dx.doi.org/10.1021/acs.jpclett.6b00781
%V 7
%X We have investigated the dynamic optical properties of CH3NH3PbI3 (MAPbI3) perovskite thin films at low temperatures using time-resolved photoluminescence, optical transient absorption (TA), and THz TA spectroscopy. Optical spectroscopic results indicate that the high-temperature tetragonal phase still remains in the MAPbI3 thin films at low temperatures in addition to the major orthorhombic phase. The fast charge transfer from the orthorhombic phase to the tetragonal phase is likely to suppress the formation of excitons in the orthorhombic phase. Consequently, the near-band-edge optical responses of the photocarriers in both the tetragonal and orthorhombic phases of the MAPbI3 thin films are more accurately described by a free-carrier model, rather than an excitonic model even at low temperatures.
@article{doi:10.1021/acs.jpclett.6b00781,
abstract = { We have investigated the dynamic optical properties of CH3NH3PbI3 (MAPbI3) perovskite thin films at low temperatures using time-resolved photoluminescence, optical transient absorption (TA), and THz TA spectroscopy. Optical spectroscopic results indicate that the high-temperature tetragonal phase still remains in the MAPbI3 thin films at low temperatures in addition to the major orthorhombic phase. The fast charge transfer from the orthorhombic phase to the tetragonal phase is likely to suppress the formation of excitons in the orthorhombic phase. Consequently, the near-band-edge optical responses of the photocarriers in both the tetragonal and orthorhombic phases of the MAPbI3 thin films are more accurately described by a free-carrier model, rather than an excitonic model even at low temperatures. },
added-at = {2016-10-05T11:57:15.000+0200},
author = {Phuong, Le Quang and Yamada, Yasuhiro and Nagai, Masaya and Maruyama, Naoki and Wakamiya, Atsushi and Kanemitsu, Yoshihiko},
biburl = {https://www.bibsonomy.org/bibtex/28b635baa80d33cc9c9abbd0a320fb8b4/gmue},
doi = {10.1021/acs.jpclett.6b00781},
eprint = {http://dx.doi.org/10.1021/acs.jpclett.6b00781},
interhash = {32ea0ad74f27e2b36f6037b572a84db5},
intrahash = {8b635baa80d33cc9c9abbd0a320fb8b4},
journal = {The Journal of Physical Chemistry Letters},
keywords = {charge-transfer perovskite phase},
note = {PMID: 27269590},
number = 13,
pages = {2316-2321},
timestamp = {2016-10-05T11:57:15.000+0200},
title = {Free Carriers versus Excitons in CH3NH3PbI3 Perovskite Thin Films at Low Temperatures: Charge Transfer from the Orthorhombic Phase to the Tetragonal Phase},
url = {http://dx.doi.org/10.1021/acs.jpclett.6b00781},
volume = 7,
year = 2016
}