Boosting Efficiency in Flexible Perovskite Solar Cells with Novel HTLs and ETLs: A drift-diffusion numerical study of CBz-PAI Interlayers and MXene Back Contacts

In this study, the functioning of flexible perovskite solar cells (FPSCs) is examined using drift-diffusion SCAPS-1D simulations under ideal conditions. The focus is on the CBz-PAI interlayer at the perovskite and hole transport layer (HTL) interface and the impact of innovative materials for HTLs, electrons transport layers (ETLs), and transparent conduction electrodes (TCOs), such as AZO and MXene, in the front and back contacts. Initially, 50 configurations of ETLs, including BaZrS₃, SnS₂, STO, WS₂, and ZrS₂, as well as HTLs such as ACZTSe, CuBiS₃, CZGS, and D-PBTTT-14, are tested to identify optimal architecture for enhancing device efficiency. The incorporation of the CBz-PAI interlayer effectively reduces interfacial charge recombination, minimizing V_OC losses and boosting overall performance. After further optimization and the integration of MXene as a back contact, the final FPSC design (PET/ITO/AZO/ZrS₂/(FAPbI₃)_0.77(MAPbBr₃)_0.14(CsPbI₃)_0.09/CBz-PAI/CZGS/MXene-V₃C₂F₂) achieves an impressive PCE of 27.17%, setting a new benchmark for FPSC efficiency.