Heat capacity features of the mixed lead halide perovskites of the MAPbX3 type
Mixing of the molecular cations offers a suitable way to manipulate both the structure and properties of hybrid halide perovskites, which are one of the most perspective optoelectronic materials nowadays. Their incredibly high efficiency is related to the interplay of several physical factors including large absorption coefficient, optimal band gap, long carrier diffusion length, low exciton binding energy and defect tolerance. From the comprehensive studies done recently [https://doi.org/10.1038/s41467-020-18938-z; https://doi.org/10.1021/acs.chemmater.1c00885;https://doi.org/10.1021/acs.chemmater.2c02807] on three types of mixed perovskites with formamidinium (FA) and dimethylammonium (DMA) of the MAPbBr3 type and ethylammonium (EA) of the MAPbI3 during this talk the focus will be on the temperature dependence of the heat capacity studies of these materials. Based on the results, a demonstration of the significant suppression of the phase transitions, enhancement of the disorder, even the indications of the glassy phases will be shown depending on the mixing levels of particular cations. The presented data will be supplemented by the resulting phase diagrams.
In-person Seminar: Donostia International Physics Center
Daria Szewczyk, Institute of Low Temperature and Structure Research PAS, Wrocław Poland and Low Temperature Laboratory, Universidad Autonoma de Madrid, Madrid, Spain