Large ionic conductivity and relaxation studies of lithium silicate nanoglasses grown into TiO2 nanoparticles

Abstract

Lithium silicate nanoglasses of composition xLi2O.(100-x)SiO2 (where x=30,40) were grown into compact of titanium dioxide nanoparticles. XPS measurements confirmed presence of Ti3+ and Ti4+ ions in the nanocomposites. The effect of TiO2 nanoparticles on lithium ion conduction was investigated in this paper. The complex conductivity spectra of lithium silicate glass nanocomposites have been measured in the frequency range of 20 Hz to 2 MHz. The temperature dependence of ionic conductivity and relaxation time obey the Vogel-Tammann-Fulcher relation. The activation energy was found to be 0.08 eV for Li+ movement in the nanoglass with x=40 due to large free volume in the nanoglass. The DC conductivity was found to be 10−5 S.cm−1 at room temperature. The formation of surface defects at the nanoglass/template interface was responsible for the lower value of activation energy. So, these nanocomposites are believed to be suitable for the fabrication of lithium-ion batteries for storage of energy.