Numerical modeling and validation of bilayer MAPbI3/FAPbI3 perovskite solar cells using COMSOL multiphysics

This work presents the COMSOL-based simulation and validation of a bilayer perovskite solar cell structured as FTO/TiO?/MAPbI?/FAPbI?/Spiro-OMeTAD/Au. The study focuses on understanding carrier transport and interfacial behavior in multilayer perovskite architectures, using a drift–diffusion model implemented in COMSOL Multiphysics. The model parameters were derived from reported experimental data in the literature, ensuring realistic representation of the physical processes governing perovskite device operation.

The bilayer configuration combines methylammonium lead iodide (MAPbI?) and formamidinium lead iodide (FAPbI?) to exploit the superior stability of FAPbI? and the higher bandgap of MAPbI?, resulting in enhanced charge extraction and reduced recombination losses. The simulated device achieves a short-circuit current density (Jsc) of 24.48 mA cm?², an open-circuit voltage (Voc) of 1.19 V, a fill factor (FF) of 79.25%, and a power conversion efficiency (PCE) of 23.08%. These results closely match the reference experimental values of 25 mA cm?², 1.16 V, 79.6%, and 23.08%, respectively, confirming the accuracy and predictive capability of the developed COMSOL model.

Following model validation, a series of parametric analyses were conducted to evaluate the effects of perovskite-layer thickness, defect density, and carrier doping concentrations in the transport layers. The donor concentration of the electron transport layer (ETL) and the acceptor concentration of the hole transport layer (HTL) were varied from 10¹? to 10²? cm?³. The results show that increasing ETL donor density enhances the built-in potential and charge collection, achieving a peak efficiency of 27.5% at 10²? cm?³, while excessive HTL doping (>10¹? cm?³) leads to reduced fill factor due to enhanced carrier scattering. This study demonstrates the reliability of COMSOL-based drift–diffusion modeling for perovskite solar cells and provides valuable insights into the optimization of multilayer perovskite architectures through controlled doping and band alignment engineering..

Dr. Kevin Abdullah is an Assistant Professor at Prince Sattam bin Abdulaziz University, Saudi Arabia. He earned his PhD in Mechanical Engineering (Nanotechnology) from the University of Waterloo, Canada. His research focuses on perovskite solar cells and nanoelectronic devices, particularly on modeling and optimization using COMSOL Multiphysics and SCAPS-1D. Dr. Abdullah has published in leading journals such as Advanced Electronic Materials, with interests spanning band alignment engineering, dielectric thin films, and high-frequency tunneling devices.