Systematic investigation of the impact of kesterite and zinc based charge transport layers on the device performance and optoelectronic properties of ecofriendly tin (Sn) based perovskite solar cells

Methylammonium tin triiodide (MASnI3) perovskite solar cells (PSC) have gained a lot of interest due to their edge over conventional Pb-based PSC in terms of less-toxic nature, wider optical absorption range and smaller bandgap. In this work, 24 novel n-i-p heterostructures of MASnI3 PSC have been analyzed in detail with various zinc-based electron transport layers (ETL) and kesterite-based hole transport layers (HTL). The proposed device architecture (FTO/ETL/CH3NH3SnI3/HTL/Back contact) performance was first enhanced by optimizing the thickness and then by the doping concentration of each layer via SCAPS-1D simulator under AM 1.5G illumi-nation. The energy band alignment of the different charge transport layers (CTL) with MASnI3 was analyzed in detail to understand its working principle. Moreover, the effects of optical absorption, band offsets, electric field, defect density, interface defects, temperature, rear reflective coating, and electrodes are monitored to charac-terize the performance of each cell structure. Among all the proposed structures, ZnO/MASnI3/CNTS based perovskite solar cell performed outstandingly well with Jsc of 29.44 mA cm-2, Voc of 1.12 V, FF of 88.82 %, and PCE of 29.24 %. These simulations provided important insights into the mechanism of carrier transport and the factors affecting the performance of solar cells. The results in this paper will help the research community in fabricating highly efficient eco-friendly solar cells.