[5p-PA3-1~46] 12.5 Organic solar cells

[5p-PA3-18] Dielectric function of Cs_0.2FA_0.8PbI_xBr_3-x perovskite from two-step reaction

〇Kotaro Takahashi¹, Takuya Miura¹, keiji Ueno¹, Hajime Shirai¹ (1.Saitama Univ.)

Keywords:perovskite, dielectric function, fine structure

We demonstrate that the fine structure and optical transition of Cs_0.2FA_0.8PbI_xBr_3-x perovsite with different x values using spectroscopic ellipsometry. XRD and PL revealed that the (110) diffraction peak shifted to higher angle and Edge emission also shifted to higher energy with increasing a Br composition ratio continupusly due to shorter lattice constant and higher bandgap energy. However, the fine structure and themagnitude of epsilon 2 of Cs_0.2FA_0.8PbI_xBr_3-x perovsite showed porous structure and lower value, respectively, at I/Br composition ratio of ~0.5.