Improvement of the Structural and Electrical Properties of the Proton-Conducting PVA-NH4NO3 Solid Polymer Electrolyte System by Incorporating Nanosized Anatase TiO2 Single-Crystal

A proton-conducting nanocomposite polymer electrolyte (NCPE) system, based on polyvinyl alcohol (PVA) as the host polymer and ammonium nitrate (NH4NO3) as the proton source, has been prepared with different concentrations of nanosized titanium dioxide (TiO2) by solution casting. The changes in the structural features related to the electrical properties have been studied using XRD analysis, which revealed that the NCPE sample with 8 wt.% TiO2 NPs exhibits the highest amorphous content. The addition of single-crystal TiO2 NPs to the proton-conducting polymer electrolyte has resulted in a remarkable enhancement of the ionic conductivity of the system. A maximum DC conductivity of 5.52 x 10(-3) S cm(-1) at 303 K has been achieved for the NCPE containing 8 wt.% of TiO2 NPs. The temperature-dependent ionic conductivity was displayed in a typical Vogel-Tammann-Fulcher-type equation, indicating a direct correlation between ionic conductivity and segmental movements of the PVA chains. The AC conductivity spectra of NCPEs have been studied in terms of the universal power law of Jonscher, and the dielectric relaxation phenomenon was analyzed using electric modulus formalism to assess if the relaxation is Debye or non-Debye type.

Automated summary

A proton-conducting nanocomposite polymer electrolyte (NCPE) system based on polyvinyl alcohol (PVA) and ammonium nitrate (NH4NO3) was prepared with different concentrations of nanosized titanium dioxide (TiO2) by solution casting. XRD analysis revealed that the NCPE sample with 8 wt.% TiO2 NPs had the highest amorphous content. The addition of single-crystal TiO2 NPs significantly enhanced the ionic conductivity of the system, with a maximum DC conductivity of 5.52 x 10(-3) S cm(-1) achieved for the NCPE containing 8 wt.% of TiO2 NPs.