This present work emphasizes the numerical modeling of lead-free methylammonium tin tri-iodide (MASnI₃)-based perovskite solar cells (PSCs) under optimizing preconditions. The prior selection of the perovskite material of MASnI₃ is feasible for a more extended absorption spectrum due to a smaller bandgap of 1.3 eV than higher bandgap methylammonium lead tri-iodide (MAPbI₃)-based PSC and the factor of lesser toxicity. Furthermore, to enhance the efficiency of the device, selecting potentially steadier and superior carrier transport materials (CTMs) is among the most effective approaches for optimizing device outputs. Among the proposed materials, a prior selection of copper antimony sulfide (CuSbS₂) and zinc oxide (ZnO) as CTMs with an optimized thickness of MASnI₃ material has offered a higher power conversion efficiency (PCE) of 22.16% under the photoillumination AM1.5. Furthermore, the less-defective PSC device can also be helpful for further device optimization and futuristic development.

Organometal halide perovskite solar cells are becoming one of the most competitive emerging technologies. They have reached a power conversion efficiency (PCE) of 22.7% in 10 years. Their high efficiency and simple fabrication process render perovskite solar cells a promising player in the field of third-generation photovoltaics. The deposition methods play an important role in the fabrication of a high quality films. In this paper, we report the preparation of methylammonium lead bromide (MAPbBr₃) thin film using a two-step method based on the transformation of PbBr₂ into MAPbBr₃ perovskite after dipping in a MABr solution. The effects of the dipping time and the annealing time on the photovoltaic, optical and structural properties of the devices were studied. The dipping time treatments of the inorganic film in organic solution were conducted from 30 s to 15 min. The obtained result showed that the PCE of the devices was improved with the increase of dipping time. In addition, an increase of annealing time induces an enhancement of the perovskite properties. Furthermore, the as-fabricated perovskite solar cell dipped and annealed for 10 min exhibited the highest power conversion efficiency of 4.8% with a short circuit current density of 16.16 mA cm⁻², an open circuit voltage of 0.84 V, and a fill factor of 35.50.

In this work, a study of a characterization technique based on open circuit voltage decay is carried out to obtain the recombination resistance of mobile charge carriers and ionic migration in triple cation perovskite solar cells. The devices were fabricated with the structure FTO/TiO₂/Cs_0.05FA_1−XMA_XPb(I_1−XBr_X)₃/spiroOMetad/Au. An equivalent circuit, created in Ngspice, was developed adjusting the capacitance and resistance values to fit the experimental open circuit voltage (V_oc) decay curves observed. The aim of this study is to associate the perovskite ionic migration with the V_oc characteristic time of charge transport in triple cation perovskite solar cells. Thus, an analysis of the open circuit voltage transient behavior was made by taking measurements of the photovoltage as a function of time. The results indicate that the technique shows charge recombination while the device is illuminated. In addition, an enhancement of the recombination resistance when increasing the FA⁺ concentration was observed. Finally, the transient behavior was associated with MA⁺, FA⁺, Cs⁺ and I⁻ migration, obtaining an ionic mobility in the range between 10⁻¹⁰ to 10⁻¹² cm² (Vs)⁻¹.

In this work, the effects of light-generated carriers on the dielectric properties of the structure ITO/PEDOT: PSS/P3HT:PC₇₀BM/Al were carried out. Impedance spectroscopy was performed at an applied bias equal to the open-circuit. From the real and imaginary part of the impedance, a dipolar relaxation type was observed, which decreased in the presence of light due to an increase in the electron mobility. The Cole–Cole diagram fit using a parallel model R-CPE equivalent circuit leads to the comparison of parallel resistances (R _p) and capacitance (CPE) in dark and under illumination. The decrease of R _p is related to the increases in the photo-generated charge carrier density. The increase in the capacitance is related to the enhancement of the P3HT/PCBM interface homogeneity.