Mesoporous TiO2-layer’s rheological impact on the perovskite solar cell performance

The rheological impact of the mesoporous-TiO ₂ (m-TiO ₂) layer was investigated, which impacted perovskite solar cell (PSC) performance. This also implies the significance of morphological variations according to the pastes’ viscosity and corresponding thickness that cause a slight influence on their bandgap and hence device photovoltaic performance. The m-TiO ₂ paste results in a viscosity of 2.85 cP with a thickness of 1 μm, indicating the bandgap of ∼ 3.55 eV. In contrast, the higher viscous paste (3.85 cP) exhibits a slightly enhanced bandgap of ∼ 3.64 nm, leading to a thickness of > 1 μm. Besides, the data obtained from these analyses were used for cell performance analysis through the SCAPS 3.3 software-based simulation with a predicted power conversion efficiency of 23.59 %. It was observed that the PSC's short circuit current density and the thickness of the m-TiO ₂ layer are inversely proportional, whereas the open-circuit voltage shows an independent effect on m-TiO ₂ viscosity. This study envisages an initial trade-off between the m-TiO ₂ layer's porosity, bandgap and thickness that can ensure the PSC with improved performance parameters.