Efficiency optimization of All-Inorganic perovskite solar cell device using NiOx and ZnO as charge transport layers

• Efficiency Optimization of an all-inorganic perovskite solar cell with the structure FTO/ZnO/CsPbBr 3 /NiO x /Au. • Employed solvent engineering techniques such as dropping solvents like IPA and EA during the spin-coating process. • Optimizing the thickness of the absorber layer and annealing conditions to enhance PCE. • After post-deposition annealing on CsPbBr 3 : PCE 0.91 % with an annealing temperature of 225 °C for 2hr. In this study, we have developed and refined an all-inorganic perovskite solar cell with the structure FTO/ZnO/CsPbBr 3 /NiO x /Au. This was accomplished by incorporating the inorganic perovskite CsPbBr 3 and the inorganic charge transport layers ZnO and NiO x . We employed solvent engineering techniques such as dropping solvents like isopropyl alcohol (IPA) and ethyl acetate (EA) during the spin-coating process, along with optimizing the thickness of the absorber layer and annealing conditions to enhance the power conversion efficiency (PCE). Our evaluation of the impact of the CsPbBr 3 absorption layer thickness on PCE revealed that efficiency improved with layer thicknesses up to 280 nm. Moreover, we investigated the influence of post-deposition annealing durations on CsPbBr 3 , experimenting with times of 0.5hr, 1hr, 2hr, 3hr, and 5hr. The optimal conversion efficiency of 0.91 % was attained with an annealing temperature of 225 °C for 2hr, particularly when the absorption layer thickness was set at 280 nm. These results suggest that the device structure optimization for all-inorganic perovskite quantum dot solar cells can be successfully applied for efficiency optimization.