Authors : Pratap Kumar Dakua, Sagar Bhattarai, Nimisha Borah, Lachit Dutta, Abhinav Kumar, Ankit Sharma, Rabinarayan Panda, Bhaben Tanti
DOI : 10.1016/j.jpcs.2026.113630
Volume : 214
Issue : 1
Year : 2026
Page No : 113630
Ruddlesden-Popper (RP) two-dimensional (2D) perovskites, however, are commonly employed as passivation layers or interfacial overlayers over 3D perovskite layers to simultaneously improve efficiency and introduce environmental stability in (Perovskite Solar Cells) PSCs under high temperatures. Conventional solution-based deposition methods also preferentially produce non-uniform 2D phases or extremely thin layers, which limit the overall efficacy of passivation. In this paper, optimized hierarchical 3D/2D perovskites are built using a Cesium germanium di-iodide dibromide, a Ruddlesden-Popper (2D) film, and (Cs0.07FA0.85MA0.08Pb(IBr)3, a 3D triple-cation. Utilizing SCAPS-1D simulations, an initial 3D perovskite absorber achieved a PCE of 29.84%. Optimization led to a maximum PCE of 30.17%, Voc of (1.3475 V), Jsc of (26.65 mA/cm2), and FF of (84.02%). This performance was attained using a 1 μm bilayer composition of Cs2GeI2Br2 and 0.25 μm Cs0.07FA0.85MA0.08Pb(IBr)3, which exhibited improved light absorption and carrier extraction than single-layer designs.