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A series of colossal magneto resistance materials having compositional formula Re_0.67Sr_0.33MnO₃ (Re = Nd, Gd, … etc.) were prepared by the sol-gel method, using Ethylene glycol as a gelating reagent. The materials were characterized by the powder X-ray diffraction technique and are found to be single phase with orthorhombic structure. The particle size of all the materials were calculated using the well known Shearer formula and are found to be in the range of 20–45 nm. In order to determine the transition temperature (T_c), the DC electrical resistivity measurements were also carried out over a temperature range 80–300 K using the four probe method and it has been observed that the T_c values are found to increase with increasing ionic size. Finally the magneto resistance measurements were also undertaken in the temperature range 80–300 K and it has been found that the MR values of these materials are better when compared with those prepared by the solid state reaction method.

The glass powder with a relatively complicated composition of 64.02SiO₂–10.05B₂O₃–7.84Na₂O–14.07ZnO–4.02Al₂O₃ (in wt.%) was first synthesized via sol–gel route. The optimal synthesis conditions for the amorphous gel are obtained. The glass transition temperature $(T_{\mathrm{\text{g}}})$ of xerogel was detected as 552${}^{\circ }$C and the glass network structure formed by the [SiO₄], [BO₄] and [AlO₄] units were confirmed by the Fourier Transform-Infrared Spectroscopy (FT-IR). The phase structure and morphologies of glass powder were characterized by X-ray diffractometer (XRD) and Field Emission-Scanning Electron Microscope (FE-SEM), the xerogels and sol–gel glasses exhibit amorphous phase when the heat-treatment temperature increases from $300^{\circ }$C to $700^{\circ }$C. The prepared glass powder with high specific surface areas and a large amount of pores contribute to the synthesis of a composite of glass-mullite-$\beta$-eucryptite at a relatively low sintering temperature of $800^{\circ }$C, which present a relatively low coefficient of thermal expansion (CTE) and high mechanical strength.

In this work, thin lead zirconate titanate, Pb[Zr${}_{0.52}$Ti${}_{0.48}$]O₃ (PZT) films have been developed from a novel sol–gel route. The sol–gel films were deposited by spin coating method. Isopropanol-based solution was used for its less toxic property. Gold (Au), platinum (Pt) and indium tin oxide (ITO) were used as substrates. Homogeneous polycrystalline films with (110) preferred orientation were obtained from all the films. The films behaved as ferroelectric material where dielectric constant at 0V for the films obtained from Au, Pt and ITO substrates were 484, 770 and 655, respectively. The coercive field values were around 10–15KV/cm which revealed that the films were soft ferroelectric.

Pure and 4.5 wt% Zn- doped SnO₂ nanopowders were synthesized by sol-gel method. These nanopowders were characterized by X- ray diffraction, Scanning electron microscopy, UV-Vis spectroscopy, I-V measurements and R-T measurements. XRD results confirmed the formation of tetragonal rutile type SnO₂ with the average crystallite size of 14 ± 1 nm which decreased to 9 ± 1 nm with 4.5 wt% Zn addition. Increase in band gap is observed from UV-Vis spectroscopy. Electrical characterizations revealed increase in resistivity with Zn addition. Temperature dependent resistance measurement showed that both the pure and the Zn- doped samples are suitable for gas sensing applications. A detailed study of these synthesized nanostructured samples is presented and discussed in the paper.