Advanced Dielectric and Impedance Spectroscopy of In ₂ Se ₂ . ₇ Sb ₀ . <sub>

Dielectric and impedance spectroscopy (20 Hz–2 MHz) of Bridgman-grown In2Se2.7Sb0.3 crystals reveals that Sb doping significantly alters electrical properties. Findings include strong low-frequency electrode polarisation, non-Debye relaxation, and conductivity transitioning from DC to correlated barrier hopping. The electric modulus formalism resolved two distinct grain and grain-boundary relaxation processes, which were not separable in the impedance data. These insights highlight Sb’s role in modifying the polarisation dynamics and charge transport in In2Se3 for advanced optoelectronic applications.