Eri Widianto, Hilman Imadul Umam, Vita Efelina, Kardiman, Deri Teguh Santoso, Muhammad Fahmi Hakim, Rossyaila Matsna Muslimawati, Eka Nurfani, Muhammad Yusrul Hanna, Natalita Maulani Nursam, Iman Santoso
Performance losses in lead-free CsSnI3 perovskite solar cells (PSCs) are dominated by interfacial recombination and inefficient hole extraction rather than limitations in optical absorption. This study investigates interface-regulated charge transport in CsSnI3-based PSCs using a multiscale simulation framework combining density functional theory and drift–diffusion modeling. First-principles calculations establish the electronic structure and optical response of CsSnI3, which are incorporated into SCAPS-1D simulations to analyze the roles of interface defects, transport resistances, and hole-selective contacts. The results indicate that voltage loss and fill-factor degradation primarily arise from defect-assisted interfacial recombination. Incorporation of graphene quantum dots (GQDs) effectively suppresses recombination and enhances selective hole extraction, yielding a PCE of 20.03% (JSC = 31.66 mA cm−2, VOC = 0.747 V, FF = 84.67%). These findings emphasize interface engineering as a key pathway toward high-efficiency, lead-free CsSnI3 PSCs. © 2026 Elsevier B.V.
Department of Physics, Faculty of Engineering, Universitas Singaperbangsa Karawang, Telukjambe Timur, Karawang, 41361, Indonesia; Department of Mechanical Engineering, Faculty of Engineering, Universitas Singaperbangsa Karawang, Telukjambe Timur, Karawang, 41361, Indonesia; Department of Chemical Engineering, Faculty of Engineering, Universitas Singaperbangsa Karawang, Telukjambe Timur, Karawang, 41361, Indonesia; Doctoral Program of Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung, 40132, Indonesia; Department of Materials Engineering, Faculty of Industrial Technology, Institut Teknologi Sumatera (ITERA), Lampung, 35365, Indonesia; Research Center for Quantum Physics, National Research and Innovation Agency (BRIN), KST Habibie, Tangerang Selatan, 15314, Indonesia; Research Center for Electronics, National Research and Innovation Agency (BRIN), KST Samaun Samadikun, Jl. Sangkuriang Cisitu, Bandung, 40135, Indonesia; Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara PO Box BLS 21, Yogyakarta, 55281, Indonesia