НАНОЧАСТИЦЫ ОКСИДОВ МЕТАЛЛОВ, ПОЛУЧЕННЫЕ НА ПОДЛОЖКАХ ПОРИСТОГО КРЕМНИЯ

Tin, iron and nickel oxides were prepared in micro porous silicon from sols. The morphology of the samples was studied using atomic force microscopy. The сross − sections of porous silicon were investigated using scanning electron microscopy. The electrical properties were investigated by impedance spectroscopy in a changing environment and temperature of gas detection reagents. The dependencies of real and imaginary components of the complex impedance were constructed in the semi − logarithmic coordinates. The method of complex plane was used for processing the experimental impedance data. Hodographs of impedance were analyzed using programs writteng in the LabVIEW environment. The experimental impedance spectroscopy data were interpreted in terms of «equivalent electrical circuit». Сonstant phase element was used to describe the resistive − capacitive properties of nanocomposite materials in the equivalent electrical circuit. The characteristic charge accumulation time in air and in the presence of reducing gases was calculated. The sensitivity to reducing gases for the real and imaginary components of the complex impedance was calculated using two methods at 300 ° C in the frequency range from 1 Hz to 500 kHz. The sensor characteristics of metal oxide films grown on single − crystal substrates, porous silicon and glass substrates were compared.