Investigations on performance parameters of graphene interfacial layer modified FASnI₃: Zn-based lead-free perovskite solar cells

The emerging and extensively approved solar technology be certainly of perovskites, by virtue of their exceptional contributions. However, their massive production senses on the remaining hurdles that are to be crossed before making them commercially diligent. This investigation highlights the measures to be taken to implement a lead free, highly stable perovskite solar cells (PSCs). The use of Zn-doped, Sn-based as perovskite (PVT) absorber layer together with graphene passivation layer at PVT/ hole transport layer (HTL) interface resulted in effective implementation of this phenomenon. In this research, a systematic numerical validation of PSC structure with FTO/ZnOS/FASnI₃:Zn/Graphene/Cu₂O/Au. The results revealed that graphene interfacial layer with adequate bandgap and electron affinity offer appreciable efficiency through proper band alignment and suppressed carrier recombination. Moreover, the recommended device contributes exceptional performance parameters: (J_sc, V_oc, FF, and η) of (20.13 mA/cm², 1.207 V, 87.13%, and 21.17%) for minimum PVT defect density of 1 × 10¹³ cm⁻³.