Ionic conductivity of sodium silicate glasses grown within confined volume of mesoporous silica template

Nanodimensional sodium silicate glasses of composition 30Na₂O.70SiO₂ has been prepared within the pores of 5.5 nm of mesoporous silica as a template using the surfactant P123. The nanocomposite was characterized by X-ray diffraction, transmission electron microscope, and X-ray photoelectron spectroscopy. Electrical conductivity of the sample was studied by ac impedance spectroscopy. The activation energy for ionic conduction was found to be 0.13 eV with dc conductivity at room temperature of 10^-6 S-cm^-1. This is attributed to the creation of oxygen ion vacancies at the interface of mesoporous silica and nanoglass arising out of the presence of Si²⁺ species in the system. These nanocomposites are expected to be useful for applications in sodiumion battery for storage of renewable energy.