Potassium tin chloride (K2SnCl6) as a lead-free perovskite: anti-solvent synthesis, structural characterization, and charge transport properties

Abstract

Potassium tin chloride (K₂SnCl₆) was synthesized using a facile antisolvent method at room temperature. X-ray diffraction (XRD) confirmed its single-phase cubic perovskite structure with the Fmm space group. Raman spectroscopy and scanning electron microscopy (SEM) further validated the structural and morphological properties. Electrical properties were Studied through impedance spectroscopy (10 Hz–5 MHz, 313–423 K), revealing thermally activated charge transport. The conduction behavior was modeled using an equivalent electrical circuit, with AC conductivity adhering to Jonscher's universal power law and exhibiting frequency-dependent dispersion. Electric modulus analysis indicated a non-Debye relaxation process. The correlated barriers hopping (CBH) model was identified as the most suitable representation of the charge-transport mechanism. Activation energies for DC conductivity and electric modulus were determined to be 0.17 ± 0.04 eV and 0.197 ± 0.07 eV, respectively, showing consistency between conduction and relaxation processes. These findings highlight the promising dielectric and ionic conductivity properties of K₂SnCl₆, positioning it as a potential lead-free material for energy storage applications. This study provides a foundation for future research aimed at optimizing its performance and exploring its use in solid-state energy storage devices.