[18p-P4-1~48] 12.5 Organic solar cells

[18p-P4-24] Acceleration of crystallization of organic-inorganic hybrid perovskite polycrystalline films at low-temperature by microwave irradiation

〇Tomoki Furuhashi¹, Masato Maitani², Shunaro Tsubaki¹, Hiroshi Segawa³, Yuji Wada¹ (1.Tokyo Tech., 2.RCAST, Univ. Tokyo, 3.Univ. Tokyo)

Keywords:perovskite, solar cell, microwave

A perovskite solar cell is a next generation solar cell using an organic-inorganic hybrid perovskite crystalline film as the light absorber, which has a high photoelectric property and can be formed by a simple coating method. To further improve the conversion efficiency, the absorption range of organic-inorganic hybrid perovskite have been tuned towards near-infrared region by introducing CH(NH₂)₂ (formamidinium: FA) for the A site cation. It, however, requires high annealing temperature, > 170 °C, for conversion of precursors into perovskite polycrystalline films. Whereas, unflavored evaporation of solvent and organic cations simultaneously occurs under high temperature annealing. Therefore, it is difficult to precisely control the perovskite conversion and simultaneously enlarge the crystals by Ostwald ripening. And consequently poor film quality is considered as an obstacle for cell efficiency. In this research, in order to promote conversion of the precursor films into the perovskite and crystalline ripening, microwave irradiation is introduced into the annealing process for crystallization. Furthermore, the effects of the waveform of irradiated microwave are also discussed for higher crystallinity.