Development of Highly Efficient ZnO Nanorod-Based Nontoxic Perovskite Solar Cell Using AZO Buffer Layer and Lanthanide Doping

In this article, we propose a design for a novel highly efficient well-aligned vertically grown ZnO nanorods (ZNRs) and lanthanide (Ln³⁺)-doped nontoxic CH₃NH₃SnI₃-based perovskite solar cell (PSC). This study reports the numerical simulation and performance optimization of novel flexible hybrid PSC using aluminum-doped zinc oxide (AZO) as a buffer layer. The proposed solar cell device is designed for the flexible substrate that consists of FTO-coated PET/AZO/ZnO-NRs/CH₃NH₃SnI₃: xLn^3+/PTAA/Au, where CH₃NH₃SnI₃, PTAA, and ZNRs are used as absorber layer, hole transport layer (HTL), and electron transport layers (ETLs), respectively. In this study, SCAPS-1D TCAD simulation tool is used, and the device fabrication procedure is also briefly explored. This study reports the optimization of several parameters, such as absorber defect density, interface defect density, and temperature. Our reported numerical simulation for the proposed hybrid PSC model exhibits ${V}_{OC}$ of 1.23 V, ${J}_{SC}$ of 21.71 mA/cm², FF of 83.95%, and enhanced power conversion efficiency (PCE) of 22.50%. We have reported that after doping of Ln³⁺ ion, the PSCs achieved ${V}_{OC}$ of 1.34 V, ${J}_{SC}$ of 22.08 mA/cm², FF of 86.83%, and PCE of 25.85%. This study highlights the promising potential of lanthanide ions doping into the absorber layer as it has remarkably improved the photovoltaic performance of the PSCs. The enhancement of PCE from 22.50% to 25.85% is highest for AZO/ZNRs ETL-based PSC structure.