Matushko I. Catalytic oxidation of hydrogen and carbon monooxide on semiconductor materials based on SnO2 modified by additives of transition metal oxides and sensitivity of corresponding sensors

The thesis is devoted to establish of accordance between catalytic activity of sensors materials with 3d-metals additives (Co, Ni, Fe, Cu) of various concentrations in reactions of the hydrogen and carbon monooxide oxidation and sensitivity of the corresponding sensors. Kinetics and mechanism of H2 and CO oxidation reactions were examined. The sensitivity of SnO2-based sensors with different concentrations of 3d-metals additives toward H2 and CO was determined.. The sensors sensitivity mechanism that takes into account the catalytic properties of corresponding sensors materials in CO and H2 oxidation was found. It is shown that the "oxygen - surface" binding energy plays a crucial role in formation of the maximal sensitivity of H2- and CO-sensors. Active catalysts of CO and H2 oxidation and H2- and CO-sensitive sensors were created. They found their application in development of adsorption semiconductor chromatographical detector and a device for determination of hydrogen in the air. The connection between the sensitivity of sensors and with oxidation reactions which take place on the sensor surface, found in this work, might be used for making new sensors with the directed sensitivity and selectivity to certain gases.