Numerical modeling and performance evaluation of non-toxic Cs2TiF6 based perovskite solar cells: A SCAPS-1D simulation study

Perovskite solar cells (PSCs) have drawn a lot of attention from researchers due to their remarkable performance, which is comparable to that of silicon-based solar cells. The toxicity and low stability of lead-based perovskite cells hinder their commercial use. To overcome this, researchers are exploring alternative elements such as tin, titanium, bismuth, antimony, and platinum as replacements for lead. In this study, non-toxic and eco-friendly perovskite Cs₂TiF₆ is utilized as an active material to mitigate the environmental impact of lead. This study mainly involves finding an optimal device with superior performance, employing extensive analysis that incorporates four different Electron Transport Layers (ETLs) and ten different Hole Transport Layers (HTLs). The numerical analysis is conducted using the SCAPS-1D simulator under an operating temperature of 300K. Initially, the study concentrates on optimizing an HTL (TiO₂:N) based on the photovoltaic (PV) performance. Subsequently, four different device structures incorporating TiO₂:N as the HTL and four distinct ETLs have been explored. Following the optimization of various device parameters, the study identifies a device structure (FTO/BaSnO₃/Cs₂TiF₆/TiO₂:N/Au) exhibiting the highest PCE of 26.8 %, V_OC of 1.74 V, J_SC of 16.68 mA/cm², and FF of 92 %. Additionally, the study conducts an evaluation of the impact of parasitic resistance, including series and shunt resistance, temperature variations, generation, and recombination effects on the four different devices.