Pressure sensitive dielectric properties of TiO₂ doped PVA/CN-Li nanocomposite

The influence of ceramic filler TiO₂ on ionic conductivity of poly(vinyl alcohol) (PVA)/chitosan (CN) blend doped with lithium perchlorate (LiClO₄) nanocomposite films were studied. The nanocomposite films were prepared by solution casting method and characterized with Fourier transform Raman spectroscopy analysis (FT-Raman), differential scanning calorimetry (DSC), and mechanical analyses. The temperature dependent ionic conductivity obeys Arrhenius rule and understood based on interpolaron hoping model. The nanoparticle size (N _p), hopping distance (R _o), exciton energy (E _ex), and conductivity (σ) of the PVA/CN-Li nanocomposite with different TiO₂ concentrations have been calculated using Brus equation. The maximum ac conductivity of 2.49 × 10⁻³ Scm⁻¹ is observed for 10 wt% TiO₂ doping level in PVA/CN-Li nanocomposite. The ionic conductivity and dielectric properties of the prepared composites with different temperature and applied pressures have been studied in detail to know the pressure sensing properties. The conduction mechanism of the composite can be represented by the correlated barrier hopping (CBH) model.