Polaronic transport in CH3NH3PbI3 single crystals

• Published in: Journal of materials science. Materials in electronics 2020-02, Vol.31 (3), p.1945-1950
• Main Authors: Jin, Lei, Qian, Yuqin, Zhang, Yipei, Bowen, Michael, Ding, Shoujun
• Format: Article
• Language: English
• Subjects: Carrier transport; Characterization and Evaluation of Materials; Chemistry and Materials Science; Hall effect; Materials Science; Minority carriers; Optical and Electronic Materials; Perovskites; Photoluminescence; Single crystals
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-019-02713-y

Organic–inorganic hybrid perovskite materials exhibit excellent features in the photovoltaic applications. However, there are still questions unanswered regarding fundamental mechanisms of high-performance perovskite devices. Hall Effect and time-resolved photoluminescence measurements are conducted in our research to reveal the nature of carrier transport in CH 3 NH 3 I 3 single crystals. We found that the high mobility of the crystals falls with increasing temperature, while the slow recombination rate constant of the crystals increases with increasing temperature. The former supports that coherent transport takes place in the CH 3 NH 3 PbI 3 single crystals, whereas the latter evidences that photo-induced minority carriers exhibit their heavy effective mass in the transport. The two apparently distinct features are complementary in the description of the nature of polaronic motions in the CH 3 NH 3 PbI 3 materials. These dynamical considerations depict a large polaron moving slowly while scattering with phonons in the CH 3 NH 3 PbI 3 single crystals.