Design and analysis of inorganic tandem architecture with synergistically optimized BaSnS3 top and AgTaS3 bottom perovskite Sub-Cells

Perovskite materials are revolutionizing the solar cell (SC) industry, continually enhancing their properties and establishing a prominent photovoltaic technology. Among these, BaSnS3 (BTS) and AgTaS3 (ATS) stand out for their strong potential as absorber layers. These inorganic chalcogenide perovskites address the drawbacks of their organic counterparts, being both lead-free and non-toxic, thereby making them highly suitable for photovoltaic (PV) applications. The exploration of BTS and ATS as absorber layers in a tandem solar cell's top and bottom cells has yielded remarkable outcomes. The innovative tandem solar cell design features a top cell structured as n-WS2/p-BaSnS3/p+-MoS2 and a bottom cell configured as n-WS 2 / p-AgTaS 3 / p +-GeS. This theoretical study using SCAPS-1D demonstrates a high efficiency of 42.57 % with a V OC of 2.03 V, a J SC of 23.29 mA/ cm2, and an FF of 89.85 %. These impressive results are achieved with adjusted layer thickness, carrier doping and defect levels, highlighting the strong potential of BaSnS3 and AgTaS3 photoactive materials. The findings reveal the viability of innovative, all-inorganic perovskite-based tandem solar cells, offering a promising avenue for future sustainable and high-efficiency photovoltaic device technologies.