Compositional Impact on Structural, Optical and Thermal Properties of Stable Cesium-Tin-Bromide-Chloride Perovskites for Optoelectronic Applications

Compositional techniques have been recognized as an efficient way to produce effective and stable inorganic halide perovskites (IHPs). In this study, AB 2 X 5 systems were created in an open atmosphere using a simple wet chemical method and a cesium-tin-bromide-chloride complex. The microstructural, optical and thermal properties of the material were investigated. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) with energy-dispersive x-ray analysis (EDAX), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), photoluminescence (PL) and thermogravimetric/differential thermal analysis (TGA/DTA) were used to investigate their properties. From the XRD data, crystalline size and strain values are calculated based on the W–H plot. We note that the crystallite size and strain decreased when SnCl 2 was substituted for SnBr 2 in the CsSn 2 Br 5 perovskite system. FE-SEM results confirmed that the elements have a good crystalline shape, and EDAX analyses revealed the elements. UV–Vis DRS confirmed that all produced perovskites have a good semiconducting nature. The energy bandgap from the Tauc plot, absorption coefficient and extinction coefficient increasing tin chloride substitution when the optical bandgap decreased were examined as part of the optical property analysis. We note that the optical bandgap is directly related to absorption and extinction coefficient values. The Pl emission wavelength center is located in the green, orange and yellow regions in the spectrum. The TGA/DTA analysis was used to determine the thermal stability. The absence of weight loss detected on the TGA thermographs reveals the non-volatility of the synthesized elements. The thermal kinetics including activation energy, Arrhenius constant, entropy, enthalpy and Gibbs energy were calculated. When SnCl 2 was added to the CsSn 2 Br 5 perovskite system in place of SnBr 2 , it was discovered that the activation energy, Arrhenius constant, entropy, enthalpy, and Gibbs energy all increased. These findings help to better understand how the AB 2 X 5 perovskite system is influenced by composition.