Modeling and Optimization\nof Modified TiO<sub>2</sub> with Aluminum and Magnesium as ETL in\nMAPbI<sub>3</sub> Perovskite\nSolar Cells: SCAPS 1D Frameworks

The perovskite device, incorporating a modified nanostructure\nof\nTiO<sub>2</sub> as the electron transport layer, has been investigated\nto enhance its performance compared to the pure TiO<sub>2</sub> device.\nVarious materials undergo electrochemical doping or treatment on TiO<sub>2</sub> to improve their photocatalytic application, thereby enhancing\nthe current density, minimizing recombination, and improving device\nstability. In this study, a numerical SCAPS simulation was employed\nto validate experimental findings from the literature. According to\nthe literature, this marks the first instance of doping Al<sup>3+</sup> and Mg<sup>2+</sup> on TiO<sub>2</sub> due to their ionic radius\ncomparable to that of Ti<sup>4+</sup>, at different doping concentrations.\nThe device was modeled and simulated with the experimental parameters\nof bandgap, series, and shunt resistances for pure TiO<sub>2</sub>, aluminum-doped TiO<sub>2</sub> (Al-TiO<sub>2</sub>), and magnesium-doped\nTiO<sub>2</sub> (Mg-TiO<sub>2</sub>). From the validated results,\nthe Al-TiO<sub>2</sub> and Mg-TiO<sub>2</sub>-based devices’\nconfigurations with minimum percentage errors of 0.427 and 2.771%,\nrespectively, were selected and simulated across nearly 90 (90) configurations\nto determine the optimum device model. Optimizing absorber thickness,\nbandgap, doping concentration, metal electrode, as well as series\nand shunt resistance resulted in enhanced device performance. According\nto the proposed model, Al-TiO<sub>2</sub> and Mg-TiO<sub>2</sub> configurations\nachieved higher power conversion efficiency values of 19.260 and 19.860%,\nrespectively. This improvement is attributed to the reduction in recombination\nrates through the injection of a higher photocurrent density.