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Thin-film hydrogen peroxide vapor sensors made from Co-doped SnO2 and La-doped ZnO were manufactured using the high-frequency magnetron sputtering method. Thicknesses of deposited doped metal oxide films were measured and their morphology was investigated. The gas sensing characteristics of the prepared sensors were measured at different concentrations of hydrogen peroxide vapors and different operating temperatures of the sensor. It was found that both sensors made from doped metal oxides SnO2 and ZnO exhibit a sufficient response to 10 ppm of hydrogen peroxide vapors at the 200 and 220 °C operating temperature, respectively. It was established that the dependencies of the response on hydrogen peroxide vapor concentration have a linear character for prepared structures at the 150 °C operating temperature and can be used for determination of hydrogen peroxide vapor concentration.

The results of research works related to the study of thick-film multiwall carbon nanotube–tin oxide nanocomposite sensors of propylene glycol (PG), dimethylformamide (DMF) and formaldehyde (FA) vapors are presented in this paper. These sensors were derived using hydrothermal synthesis and sol–gel methods. Investigations of response–recovery characteristics in the 50–300 °C operating temperature range reveal that the optimal operating temperature for PG, DMF and FA vapor sensors, taking into account both high response and acceptable response and recovery times are about 200 and 220 °C, respectively. The dependence of the sensor response on gas concentration is linear in all cases. Minimal propylene glycol, dimethylformamide and formaldehyde gas concentrations, where the perceptible signal was noticed, were 13, 5 and 115 ppm, respectively.

The InAsSbP quantum dots were grown on InAs(100) substrate by modified version of liquid phase epitaxy. The morphology, dimensions and distribution density of the quantum dots were investigated by an atomic force microscope. Two mid-infrared photodetectors made of InAs(100) substrate with and without InAsSbP quantum dots are fabricated and investigated. Current-voltage characteristics are measured and a deviation from linearity is detected for the quantum dot photodetector. Room temperature photoresponse spectra at low applied voltages are investigated. An anomalous photovoltaic effect is detected. Open circuit voltage and short circuit current generated in the quantum dot photodetector under irradiation of He-Ne laser operating at 3.39 microm are measured. Our measurements showed that voltage and current responsivities at room temperature are equal to 2 V/W and 82 mA/W, respectively. Specific dips in the quantum dot photodetector's room temperature capacitance-voltage characteristics are observed. Magnetic field up to 1.6 T was applied to measure the magnetoresistance at room temperature. Specific oscillations on magnetoresistance curve for the quantum dot photodetector are observed.