The influence of palladium doping on the structural, morphological, optical and electronic properties of formamidinium lead iodide perovskite films

In this study, we investigated the effects of palladium (Pd) doping on the properties of formamidinium lead iodide (FAPbI3) perovskite films. Pd was doped at concentrations ranging from 0.5 to 2 % and coated onto indium tin oxide (ITO) glass substrates using a spin-coating technique. The crystal structure of the films was characterized using X-ray diffraction (XRD), revealing that Pd-doping reduces the hexagonal phase while increasing the cubic phase in the FAPbI3 lattice. The optical properties were evaluated using ultraviolet–visible spectrophotometry (UV–Vis), showing changes in light absorption and a reduction in the energy gap with Pd incorporation. Scanning electron microscopy (SEM) was employed to examine the morphological properties of the films, indicating significant surface alterations and formation of larger grain sizes due to Pd incorporation. The electronic structure of perovskite films was thoroughly investigated using X-ray photoelectron spectroscopy (XPS). These findings demonstrate that Pd-doping significantly affects the structural, optical, and electronic properties of FAPbI3 perovskite films, with potential implications for enhancing the performance of perovskite-based devices.