Impact on green energy conversion and stability of PSC device with the insertion of bifunctional molecule as an interfacial layer

Abstract

Organometallic-halide perovskite solar cells (PSCs) are currently considered the most promising solar cell devices for the next generation. PSCs utilizing formamidinium lead triiodide (FAPbI3) have showcased exceptional capabilities as an efficient light absorbers in the realm of thin-film photovoltaics. This study encompasses a comprehensive analysis of two device configurations: FTO/TiO2/FAPbI3/CBz-PAI/Spiro-OMeTAD/Au and FTO/TiO2/FAPbI3/Spiro-OMeTAD/Au through computational modeling and performance optimization. By introducing CBz-PAI as a defects passivation layer at the perovskite/Spiro-OMeTAD interface, we aim to enhance the performance and improve the stability of the above mentioned solar cell devices and examine the influence of the CBz-PAI layer. The performance of both devices was thoroughly analysed by examining the effect of variations in perovskite, electron transport layer (ETL), and hole transport layer (HTL) thickness, perovskite doping concentration and defect density, electron affinity as well as series and shunt resistance. Additionally, the impact of band gap and temperature on the devices were evaluated. Furthermore, different ETLs and HTLs were tested to optimize both device configurations and enhance their performance and stability. The simulation results revealed that the device architecture consisting of FTO/WS2/FAPbI3/CBz-PAI/CuI/Au exhibited the highest power conversion efficiency (PCE) among all the different configurations. The estimated values of open circuit voltage (VOC), short circuit current density (JSC), fill factor (FF) and PCE of the designed PSC were found to be 1.186 V, 28.19 mA/cm2, 80.57 % and 26.93 % respectively. Overall, this thorough simulation, supported by the validation results, demonstrated the capability of FAPbI3 absorber with CBz-PAI as defect passivator. WS2 and CuI as ETL and HTL, respectively, facilitating the pathway for the advancement of cost-effective, stable and efficient FAPbI3 PSCs in the photovoltaic industry.