Effect of phthalocyanine-based charge transport layers on unleaded KSnI3 perovskite solar cell

The implementation and commercialization of perovskite solar cells (PSCs) are hindered due to the presence of toxic lead. Metal phthalocyanines (MPc) have been studied extensively as charge transport layers (CTLs) in PSCs due to their desirable properties such as thermal and chemical robustness, and low production cost. In the present work, a theoretical study of the effect of phthalocyanine-based CTLs on a non-leaded KSnI3-based PSC is carried out using SCAPS software. The defect concentration of the layers and the interfaces, doping density and thickness of the layers, shunt, and series resistance of the device is optimized. Carbon is suggested as an affordable alternative to the state of art back contact material, gold. The stability of this device with temperature is also established. The optimized solar cell showed an excellent fill factor (FF) of 86.51% with a power conversion efficiency (PCE) of 11.91% and an excellent quantum efficiency (QE) ranging from 99.42%(400 nm) to 72.02%(660 nm) in the visible region. The present study highlights the enhanced performance parameters of leadless KSnI3-based PSC with phthalocyanine-based CTLs as compared to the state-of-art CTLs, TiO2 and Spiro-OMeTAD reported in previous literature with a PCE and FF of 9.776% and 36.139% respectively.