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Monodispersed CuO octahedral crystals were successfully synthesized using a low-temperature co-precipitation method. Zinc doping in CuO created surface defects that enhanced oxygen adsorption on the surface crucial for gas sensing applications. Pure and Zn-doped CuO sensor films were realized using the doctor blade method. The sensor films showed selective response towards a low concentration of NO2 at a lower operating temperature of 150 °C. Doping with Zn causes the resistance of the sensor film to decrease due to the enhancement of charge carriers with an analogous improvement in the sensor response. The observed decrease in sensor resistance agreed well with the findings of the work function studies. Zinc doping resulted in an increase in work function by 180 meV which, after NO2 exposure, was found to increase by a further 130 meV, attributed to the oxidizing behavior of the test gas.

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For realizing high power generator efficiency based on thermoelectricity, Si, Ge and SiGe nanostructures have attracted attention. In this paper, we have investigated a new approach to fabricate an ultrathin polycrystalline SiGe-on-insulator (pc-SGOI) substrate by a simple process based on Si and Ge deposition followed by thermal diffusion suitable for thermoelectric devices. A 45-nmthick SGOI layer with a Ge fraction of nearly 0.45 was fabricated, and the Ge fraction was homogeneous in plane over the layer. Its thermal conductivity was 0.87 W mK −1 , lower than that of a single-crystalline SGOI layer. This is caused by the enhancement of scattering of phonons at grain boundaries in the pc-SGOI layer.

Abstrllct-Gas sensing properties of pure and surface modified ZnO nanowires towards HzS gas have been investigated. The hydrothermally grown ZnO nanowires network has been selectively modified with various sensitizers using RF sputtering to generate a 2X7 sensor array. After fabrication, the sensor array device has been investigated for its gas sensing properties. The optimal temperature for HzS sensing has been observed to be 300°C. The maximum sensor response of S=52 was obtained for AUS.7at% modified ZnO NWs with response and recovery times of 22 sec and 52 min, respectively. Concentration profile at 300°C revealed the same pattern with change in amplitude by changing HzS concentration. The sensor array was able to detect HzS both qualitatively and quantitatively based on the graphical pattern and position of the pattern, respectively.