Device simulation of CaZrS3 perovskite solar cell for different hole-transporting materials using AMPS-1D

Device simulation evaluation, utilizing AMPS-1D, demonstrated for CaZrS 3 -based perovskite solar cells featuring three distinct hole transport layers (HTLs): Cu 2 O, Cu–NiO, and CuO. Analysis of the energy band diagram indicated that Cu 2 O provides the optimal valence band alignment with the CaZrS 3 bulk layer. Cu 2 O provides better hole extraction and lower recombination losses, while Cu–NiO and CuO show increased recombination losses. The parameters of the device were determined for various bulk defects in CaZrS 3 as well as for interface traps at the CaZrS 3 /HTL boundary. The increased trap densities lead to trap-assisted recombination, which damages all device parameters. For an optimal interface trap level at 3.7 × 10 16 cm −2 , the cell featuring a Cu 2 O layer provides Voc≈1.0 V, Jsc≈35 mA/cm 2 , FF ≈ 82–86%, and PCE≈30%, surpassing Cu–NiO and CuO layers. The ideal thickness for the CaZrS 3 perovskite layer and Cu 2 O was determined to be 250 nm and 150 nm, respectively, resulting in a peak PCE of approximately 30%. Note that this ∼30% efficiency is the fully co-optimized result, reached after sequentially optimising absorber thickness, interface trap density, and Cu 2 O thickness/back-contact. The thickness-only optimum level is ∼26%. The external quantum efficiency of Cu 2 O-based cells surpasses 90% for λ = 400–700 nm, demonstrating its enhanced carrier collection over Cu-NiO and CuO. At higher temperatures, Cu 2 O exhibits improved thermal stability and maintains the highest initial PCE (∼30% at 250K to ∼22% at 400K) more effectively than Cu–NiO and CuO. Ultimately, back-contact analysis indicates that Pt (Φ = 5.7 eV) is the superior top electrode with PC around 30% because of better energy alignment in contrast to Ag (Φ = 4.8 eV), which has a lower PCE of about 24%. Our study indicated that Cu 2 O proves to be a strong HTL for CaZrS 3 -based perovskite solar cells, offering superior performance metrics and thermal stability.