Heterojunction active layer MAPbI3/CsPbI3 design for high-performance perovskite solar cells: a computational analysis achieving 20.5% efficiency

Abstract

This simulation study employed three distinct perovskite solar cell (PSC) structures: double electron transport layer (DETL) composed of (10–50 nm) TiO₂/ (50 nm) ZnO, double hole transport layer (DHTL) incorporated of (20–100 nm) MoO_x/ (200 nm) Spiro-OMeTAD, and double active layer (DAL) consisted of (300 nm) MAPbI₃/ (50–150 nm) CsPbI₃ based PSCs separately. These configurations aimed to increase the charge carrier population and enhance fast electron and hole injection toward the electrodes in PSCs-based MAPbI₃. Then, a morphological simulation study was conducted to evaluate the spatial distribution of the electron charge carrier density within the ETL, HTL, and perovskite materials. Additionally, the investigation delved into charge carrier density, charge carrier generation, and recombination within the thin-film materials, and compared the performance of single and doubling layers in PSCs. Notably, the simulation results demonstrated a remarkable power conversion efficiency (PCE) of 20.52% for the heterojunction active layer structure, surpassing the PCE of 19.8% and 18.5% were achieved for the DHTL and DETL configuration, respectively. Moreover, the PCE of the cell enhanced by 29% with the DAL (300-nm MAPbI₃/150-nm CsPbI₃) structure compared to the reference cell. This study provides meaningful information for advancing the realm of high-efficiency planar PSCs founded on double absorber layer structure.