Optical characteristics and solar cell performance of (MAPbBr<inf>3</inf>)<inf>x</inf> ((MACl)<inf>0.28</inf>FA<inf>0.98</inf>Cs<inf>0.02</inf>PbI<inf>3</inf>)<inf>1−x</inf> with various composition ratios

Abstract

Perovskite solar cells were prepared using (MAPbBr3)x ((MACl)0.28FA0.98Cs0.02PbI3)1 − x, (x = 0, 0.05, and 0.07) perovskite layers. The effect of the MAPbBr3 amount on the formed phases and lattice parameters of the formed perovskite films was explored using the x-ray diffraction technique. The grain size of the film was increased from 64 to 71 nm as MAPbBr3 was added to the formed films. The direct optical band gap was increased from 1.54 to 1.57 eV as MAPbBr3 was added to the perovskite film. In the visible range, the refractive index value of the film with 5% MAPbBr3 is slightly larger than that of the films with 7% MAPbBr3. The effect of adding MAPbBr3 on absorption, transmittance, reflectance, extinction coefficient, refractive index, dielectric constant, loss energy functions, nonlinear optical parameters, and emitted photoluminescence spectra of the different films was investigated using the UV–vis spectroscopy technique. The cell without MAPbBr3 exhibited an open circuit voltage (Voc) of 0.82 V, a short current density (Jsc) of 22.4 mA/cm2, a fill factor (FF) of 65%, and power conversion efficiency (PCE) of 11.8% while the cell with 5% MAPbBr3 exhibited the highest PCE of 17.2% with a VOC of 1.01 V, a JSC of 23.6 mA/cm2, and a FF of 72%.