Numerical and Experimental Validation of CsPbBr₃ Perovskite Solar Cells: Insights on a One-Step Deposition Technique

Perovskite solar cells (PSCs) have gained considerable attention in recent years as highly efficient and low-cost alternative to conventional photovoltaic technologies. In this study, we focus on CsPbBr3-based PSCs, through a combination of numerical simulations and experimental validation to explore their potential under illumination. We systematically investigated various charge transport layers, the highest PCE of 8.34% achieved using TiO2 as the ETL with Spiro-OMeTAD serving as the HTL in combination with the CsPbBr3 absorber layer. By analyzing energy band diagrams, we assessed the influence of absorber layer thickness, acceptor density, and defect densities on device efficiency, presenting the results as contour plots. We optimized these parameters, including interfacial defect densities at both the ETL/absorber and absorber/HTL interfaces using a simulation approach. Furthermore, we examined the effects of electron affinity, temperature, series and shunt resistance, capacitance, Mott–Schottky characteristics, generation rate, and recombination rate to gain a deeper understanding of the optimized device’s performance. Subsequently, we experimentally fabricated CsPbBr3-based PSC devices using a one-step spin deposition technique, which is the first attempt of its kind for this material system, to the best of our knowledge. The CsPbBr3 films were analyzed by using XRD, SEM with EDX, UV–visible, and PL spectroscopy. We then fabricated the devices based on the optimized design from our simulations and measured J–V characteristics and EQE curves. The performance of the experimental devices was further validated by the simulation outcomes for the CsPbBr3-based PSC device. The present work underscores the potential of PSCs based on CsPbBr3 and offers significant perspectives for their enhancement and subsequent progress in the field of photovoltaics.