Asymmetric effects of interfacial defects, recombination velocity, and temperature on perovskite solar cell performance

Abstract Perovskite solar cells (PSCs) have achieved efficiencies nearing 30%, but interfacial recombination remains a critical challenge. This study employs Atlas TCAD finite element simulations to investigate the combined effects of surface recombination velocity (SRV, 10 to 10 7 cm.s −1 ) and interfacial defect density (N t , 10 14 to 10 17 cm −3 ) on PSC performance across four architectures: TiO 2 or SnO 2 as electron transport layers (ETLs) and NiO or Spiro-OMeTAD as hole transport layers (HTLs). The results reveal a significant asymmetry: the ETL/perovskite interface is highly sensitive to recombination losses, with TiO 2 -based devices showing greater degradation than SnO 2 -based ones, while the perovskite/HTL interface remains robust. The SnO 2 /NiO configuration achieves the highest performance, with a power conversion efficiency (PCE) of 22.59%, open-circuit voltage (V oc ) of 1.08 V, short-circuit current density (J sc ) of 24.25 mA.cm −2 , and fill factor (FF) of 85.51% at SRV = 10 cm.s −1 . NiO-based devices outperform those using Spiro-OMeTAD, particularly at high defect density, and exhibit enhanced stability at moderate temperatures (40 °C–55 °C). Temperature-dependent analysis shows that TiO 2 /perovskite interfaces degrade above 55 °C, highlighting the need for targeted passivation. These findings guide PSC optimization by recommending SnO 2 /NiO architectures, ETL interface passivation (e.g., with Al 2 O 3 ), and thermal management at 40 °C–55 °C to maximize efficiency and stability for sustainable energy applications.