Optical Properties of Bromine-Doped Perovskite Films

The optical properties of bromine-doped organic-inorganic perovskite thin layers were investigated. Replacing iodine, which is component of perovskites, with bromine improves film properties due to the formation of a more stable crystal structure. In this study, perovskite films MAPbI2Br, MAPbBr3, FAPbI 3-x Br x , FA 0,85 Cs 0,15 Pb(I 0,85 Br 0,15 ) 3 and Cs0,05(FA x MA 1-x ) 0,95 PbI y Br 3-y , were obtained by spin-coating method. To determine the optimal technological parameters, such as the spin-coating speed, annealing time and temperature, we studied the photoluminescence and absorbance spectra of the created films. It was found that the use of an antisolvent leads to an increase in the photoluminescence intensity, which can be attributed to the formation of a better-quality film with fewer defects.