Proceedings of MATSUS Fall 2024 Conference (MATSUSFall24)
Publication date: 28th August 2024
A novel approaches to studying hybrid perovskites optical properties has been proposed to complement commonly used ones. In the study a piezo-modulation spectroscopy was applied to investigate the optical transitions in well-known perovskite films. A series of methylammonium and formamidinium perovskite layers were prepared using spin-coating and drop-casting directly onto a piezoceramic substrate. The piezoreflectance signal, corresponding to optical transition, was successfully observed at room temperature. Subsequently, to explore the phase transitions in MAPbI3 in detail, measurements were conducted over a wide temperature range for layers prepared by both drop-casting and spin-coating techniques. Complementary photoluminescence measurements were also conducted as a reference method. The energies of optical transitions obtained from absorption-like (i.e., piezoreflectance) and emission-like (i.e., photoluminescence) experiments are in a good agreement. The applied piezoreflectance method demonstrated greater sensitivity to phase transitions in the standard MAPbI3 perovskite compared to photoluminescence due to the intrinsic sensitivity of this method to structural phase transitions. A comparative analysis of these two measurement techniques revealed that utilizing piezo-modulation spectroscopy for exploring halide perovskite semiconductor properties provides valuable insights into the optical properties of MAPbI3.
This work was supported by the National Science Centre (NCN) Poland PRELUDIUM BIS 4 no. 2022/47/O/ST3/01965.