Impedance spectroscopy of multicomponent Se-Te-Sn-In chalcogenide glass ceramics

The present research investigates the influence of indium incorporation (2%, 4%, and 6%) in Se_78-xTe₂₀Sn₂In_x chalcogenide glass-ceramic alloys on electrical impedance spectroscopy, complex modulus, and temperature-dependent conductivity across a broad frequency range (0.1–500 kHz) and temperature window (300–333 K). The impedance response, analyzed using equivalent circuit modeling, reveals a transition from a single to a double semicircular arc, indicating contributions from both grain and grain boundary regions. A distinct non-Debye relaxation behavior and negative temperature coefficient of resistance (NTCR) are observed, highlighting thermally activated charge transport. The activation energy derived from relaxation time and AC conductivity follows Arrhenius trends, while the Meyer-Neldel rule confirms entropy-assisted hopping conduction. The shortest relaxation time (∼10⁻¹¹ s) and moderate activation energies (0.26–0.34 eV) suggest excellent dielectric responsiveness and rapid polarization, favorable for energy storage and conversion devices. These results underscore the potential of indium-doped Se-Te-Sn glasses as functional layers in next-generation thermoelectric modules, supercapacitors, and solid-state ionic conductors for energy applications.