Fabrication and characterization of methylammonium lead iodide-based perovskite solar cells under ambient conditions

Abstract

This study investigated the fabrication and characterization of CH₃NH₃PbI₃ based perovskite solar cells (PSCs) using the one-step spin coating technique under ambient conditions, eliminating the need for expensive glovebox and thermal evaporation equipment. The perovskite layer was annealed at 65 °C for 30 seconds and 100 °C for 30 seconds, 1 and 2 minutes. The scanning electron microscope (SEM) images show a smooth and uniform surface coverage for the ETL and CH₃NH₃PbI₃ layers. SEM results also show an average grain size of 397 nm for CH₃NH₃PbI₃ and an average particle size of ~17 nm for TiO₂ was confirmed by transmission electron microscopy (TEM). X-ray diffraction (XRD) results confirmed the formation of tetragonal perovskite (CH₃NH₃PbI₃) phase with high crystallinity with a crystallite size of 19.99 nm for the samples annealed for 30 seconds at 65 °C and 1 min at 100 °C. FTIR results also confirmed the presence of anatase TiO2 at wavenumber 438 cm^-1 and the formation of the adduct of Pb₂ with dimethyl sulfoxide (DMSO) and MAI is confirmed at 1,015 cm^-1 . From the Tauc plot the bandgap energy of TiO2 and Perovskite layers was determined to be 3.52 eV and 2.06 eV respectively. An open-circuit voltage was 0.9057 V and short circuit current density was 12.2185 mA/cm² with a fill factor of 48.05 and power conversion efficiency (PCE) of 5.199%.