Numerical Assessment of CsXY3 (X = Ge, Sn; Y = Cl, Br, I) Perovskites Unified with NiO and Zn(O0.25S0.75) for Solar Cell Applications

Future energy harvesting systems need a sustainable perovskite solar cell having low cost and good power conversion efficiency (PCE). Herein, the perovskite CsXY 3 (X = Ge, Sn; Y = Cl, Br, I) absorber layer, nickel oxide (NiO) hole‐transport layer, and zinc oxysulfide (ZnO 0.25 S 0.75 ) electron‐transport layer‐based solar cell devices are investigated using SCAPS‐1D numerical simulations. The CsXY 3 solar cell devices performance is assessed by estimating the effects of ample parameters, such as thickness, doping concentration, bulk defects, thickness, and defects at NiO/CsXY 3 and CsXY 3 /Zn(O 0.25 S 0.75 ) interfaces. The Au/NiO/γ‐CsSnI 3 /Zn(O 0.25 S 0.75 )/FTO device structure shows a low open‐circuit voltage ( V OC ) ≈1.0580 V, high fill factor ≈88.14%, excellent PCE ≈31.40%, and reasonable short‐circuit current density ( J SC ) ≈33.68 mA.cm −2 . Further, the impact of series/shunt resistances and temperature discloses upright reliability of the Au/NiO/γ‐CsSnI 3 /Zn(O 0.25 S 0.75 )/FTO device structure suitable for cost‐effective solar cell device applications.