Almahsen, S. B.; Al-Dahash, G. A. Breakthrough 31.25% Efficiency in Lead-Free Double Perovskite Tandem Solar Cells: A Novel Cs₂AgBi₀.₇₅Sb₀.₂₅Br₆ CsSnI₃ Design via SCAPS-1D Simulation. J Theor Appl phys 2026, 20 (4). https://doi.org/10.57647/jtap.2026.2004.04.