Pollution Control and Sustainable Environment

Biography

Biography: O.G. Kuzminykh

Abstract

One of the environment protection important problems is a detection of oxidizing gases in the ambient air. Three out of six common air pollutants (also called as “criteria pollutants”) are oxidizing gases: nitrogen oxides, low level ozone (or tropospheric ozone), and sulfur dioxide. Breathing ozone and nitrogen oxides can trigger a variety of human health problems, particularly for children, the elderly, and people who have lung diseases. Therefore, monitoring of O₃ and NO_x concentration in the ambient air is a critical task for human health protection. For these reasons, the various types of the binary, ternary and quaternary metal-oxide semiconductors have been widely studied for oxidizing gas detection.Thin films of palladium oxide are set forth as promising material for oxidizing gas detection. PdO thin thin films were prepared by thermal oxidation at dry oxygen of previously formed Pd layers on different substrates. By high-energy electron diffraction and X-ray analysis it has been established that oxidation of initial Pd layers at T = 770 - 1070 K led to formation of homogenous polycrystalline PdO films. At ozone detection PdO films prepared by oxidation at T = 870 K have shown the good values of sensitivity, signal stability, operation speed, and reproducibility of sensor response. At ozone concenteration interval ~100 – 250 ppb the values of sensor response S varied from S = 8.5 to S = 14.2. In comparison with other materials, palladium oxide thin films have some advantages at gas sensor fabrication. Firstly, at rather low operating temperatures PdO films have shown good values of functional parameters. Secondly, the synthesis procedure of binary PdO films is rather simple and is compatible with planar processes of microelectronic industry.