Ezequiel Paz Totolhua

This research study conducts a computational analysis of a two-terminal (2T) Perovskite-on-silicon (PVK-Si) solar cell with a tandem configuration. The motivation for this analysis arises from the outstanding potential of PVK-Si solar cells to surpass the efficiency limitations of conventional photovoltaic technology. The tandem configuration utilizes a combination of CsSnBr₃ in the top sub-cell and crystalline silicon (c-Si) in the bottom sub-cell. After optimizing parameters of the top sub-cell (FTO/TiO₂/CsSnBr₃/rGO/Au), which included the thicknesses of CsSnBr₃ (500 nm), TiO₂ (40 nm), rGO (50 nm), the interface defects (10¹³ cm⁻²), and the bandgap of CsSnBr₃ (1.78 eV), the PVK-Si tandem device was simulated. As a result, the top CsSnBr₃ sub-cell achieved an efficiency of 21.62%, while the bottom silicon sub-cell achieved an efficiency of 23.48%. Subsequently, the sub-cells were interconnected in series using filtered spectra and current-density matching. After interpolating the J-V curves, the tandem exhibited a global efficiency of 29.76%, a fill factor (FF) of 85.30%, a matched current density (J_SC) of 19.02 mA/cm², and an open-circuit voltage (V_OC) of 1.83 V. The EQE results confirmed efficient photon management via complementary sub-cell absorption. The performance is competitive with experimental lead-based tandems and exceeds that of current lead-free simulations. Therefore, this research proposes a viable pathway for the development of non-toxic, cost-effective tandem solar systems with manufacturing capabilities.

Mixed-halide perovskites enable the creation of high-performance and low-cost solar cells. Chloride incorporation enhances film morphology, carrier diffusion length, and stability, improving device performance. Nevertheless, optimizing film thickness, defect density, and metal contact work function remains insufficiently explored, despite its potential to enhance power conversion efficiency. In this study, a numerical simulation was performed using SCAPS-1D (version 3.3.10) to identify the optimal parameters for the FTO/TiO₂/CH₃NH₃Pb_3−xCl_x/Spiro-OMeTAD/Au configuration. The best performance parameters that have been published in the literature based on experimental results are as follows: V_OC = 1.077 V, J_SC = 21.45 mA/cm², FF = 77.57%, and PCE = 17.97%. In contrast, the performance parameters obtained from numerical simulations for the same structure are V_OC = 1.28 V, J_SC = 21.63 mA/cm², FF = 78%, and PCE = 21.53%. In our numerical analysis, we achieved efficiencies that were comparable to those reported in experimental studies, and after optimization, superior performance parameters were attained, including V_OC = 1.179 V, J_SC = 27.26 mA/cm², FF = 81.03%, and PCE = 26.07%. These results indicate that optimized parameters can be integrated into the design and fabrication of mixed-halide perovskite solar cells to enhance performance.

In this research work, an inverted p-i-n type perovskite solar cell: ITO/PEDOT: PSS/CH3NH3PbI3/PCBM/Au has been simulated and optimized in SCAPS-1D. The optimized parameters in SCAPS-1D that improved solar performance were: perovskite thickness, the total defect density of perovskite, the total defect density of interfaces, series and shunt resistances, and device operating temperature. As a result, the efficiency (PCE) increased to 18.33%. Subsequently, when the silicon-rich oxide (SiOx) material was implemented in the simulation as downconversion energy material on the outside of the cell, a power conversion efficiency (PCE) of 23.7% was obtained. The SiOX film obtained experimentally by sputtering obtained good photoluminescence, absorption coefficient, band gap, and transmittance characteristics before and after thermal annealing. These characteristics have been considered for the proposed device. It is indicated that the inverted perovskite solar cell of type pi-n: SiOx/ITO/PEDOT:PSS/CH3NH3PbI3/PCBM/Au has better J-V output values and EQ quantum efficiency than the perovskite solar cell without SiOx.