Synthesis of Perovskite Thin Films (FAPbBr1.6I1.4) by Spin Coating Technique for Tandem Solar Cells

摘要

In this work, we have optimized the deposition parameters of the FAPbBr1.6I1.4 perovskite thin films by the spin coating technique, namely the deposition speed and the centrifugation time. The thin layers of perovskite FAPbBr1.6I1.4 were prepared by mixing the solution of PbBr2: DMF: DMSO and FAI: IPA and deposited on glass substrates by the one-step spin coating technique. Morpho-structural and optical techniques were used for the characterization of fabricated thin films. The results show that the variation of the speed and the centrifugation time has a significant effect on the morphology and optical properties of the FAPbBr1.6I1.4 perovskite thin films. The structural characterization of the FAPbBr1.6 I1.4films revealed the presence of the perovskite structure in a single cubic $lpha-mathrm{FAPbBr}_{1.6}mathrm{I}_{1.4}$ phase independently of the deposition conditions. The optimized thin film was deposited by spin coating at 4000 rpm during 30s has a band gap energy of 1.83 eV. Such a gap suitable for a top cell as tandem configuration with silicon bottom cell.