Investigation of mixed bromide iodide lead perovskites by spin coating onto single and tandem solar cells applications

[EN] In this study mixed bromide iodide lead perovskites CH3NH3PbI3-xBrx were successfully deposed at Fluorine doped Tin Oxide (FTO) coated glass substrate by Spin coating process. We investigated the processing substitution of PbI3 by PbBr3 in CH3NH3PbI3-xBrx.We also studied the structural and optical properties in Br-gradient MAPbI3-xBrx perovskites thin film deposited using UV-vis absorption and X-ray diffraction of each mixed halide (I/Br) perovskites film and nanostructured for solar cell applications. The surface morphology of mixed halide perovskite films deposited was analyzed by Scanning electron microscopy (SEM). We observed that peaks are shifted toward the higher 2 theta direction as Br content increases, moving from a tetragonal to a cubic structure. The perovskite films deposited show bandgap increasing with Br content. We also used device simulation to study the impact of various compositions of Br on single, and tandem proposed solar cells' performance. In consideration of the Br rate, the suitable device for adequate Br rate in solar cell application has been considered. The tandem J-V shows a short-circuit current density (Jsc) of 38.81 mA/cm2, an open-circuit voltage (Voc) of 1.54 V, fia ll factor (FF) of 73.32 % a,nd Pa CE of 43.84 %.