Varistor response and structural analysation of silver mixed TiO₂ (anatase) nanoparticles

In this research work, composite mixtures of TiO₂ (anatase) and silver were investigated. The nano-scaled sample powders of anatase-TiO₂ and Ag were synthesised using ultrasonic assisted sol-gel method and top-down method respectively. The content of silver was increased gradually to observe its effect on varistor properties of TiO₂ nanopowders. Structural and surface analysis were done using various characterisation. TGA gave the calcination temperature at 450 °C in order to obtain anatase form. Slender tetragonal structure belonging to \({D}_{4h}^{19}\) $D_{4h}^{19}$ I4₁/amd space group and cubic structure in \({\text{O}}_{\text{h}}^{5}\text{Fm}3\text{m}\) ${\text{O}}_{\text{h}}^5\text{Fm}3\text{m}$ space group were obtained for TiO₂ and Ag respectively. These results were confirmed from XRD and Raman Analysis. FESEM exhibited spherical shape for TiO₂ nanopowders and also showed the cluster formation of Ag. Current versus voltage graphs were obtained to examine the extent of applicational prospects and it was observed that TiO₂ sample mixtures gave small increase in current voltage values when used with single conductive material.