[13p-P9-1~38] 12.5 Organic solar cells

▲ [13p-P9-33] Positional Fluctuation of Photoconductivity in Lead Iodide Perovskite films Evaluated by Spatial- and Time-Resolved Microwave Conductivity

〇(M1)Frank Elias Caraballo¹, Masataka Kumano¹, Akinori Saeki^1,2 (1.Osaka University, Graduate School of Engineering, Applied Chemistry, 2.JST-PRESTO)

Keywords:Perovskite, TRMC, AFM

Lead halide perovskite is a diverse electric platform, and a growing number of studies have made use as an efficient and cost-effective solar cell. However, the electronic behavior directly relating to the device performance is complicated and still under debate, which includes hysteresis, enhancement/degradation during operation, susceptibility to environmental factors, and batch-to-batch fluctuation. We have investigated charge carrier dynamics in CH3NH3PbI3 perovskite by using time-resolved microwave conductivity (TRMC), revealing the high local mobility, reduced recombination, and low trap density.[1] It was found that the crystal size, changed by preparation method (1-step or 2-step) and underlying scaffolds (TiO2 or Al2O3), are correlated with the minimum sum of the charge carrier mobilities (Σ µ min). The TRMC signal is, however, an average value within an exposing laser spot (e.g. 5 mm in diameter). The local fluctuation of perovskite film quality may hide the subtle change in its optoelectronic property.