GAS DETECTION METHOD USING CHEMISORPTION AND PHYSISORPTION

摘要

various types of gas are detected with the aid of a capacitor having a dielectric solid ionic excited by a voltage of the alternating current of the order of 0.1 to 30 hz with an amplitude of 1 to 100 millivolts, allowing the development of methods of physical adsorption and / or u no ac voltage having a frequency in the same order and amplitudes between 0.1 and 3 volts for reactions of chemical adsorption. the ac impedance of the capacitor is detected in the case of excitation of the physical adsorption and chemical adsorption to determine the type and the concentration of the gas.in the chemical adsorption, an activity similar to that of a diode occurs and is detected by the ac current harmonic detection methods.the surface of the dielectric is affected by the gas is covered by a porous electrode or grid inert metal or a catalyst which causes the capacitor to trigger the preferential adsorption of certain materials for the dielectric in order to indicate the presence of some ga z.a plurality of capacitors having different characteristics of adsorption of different gases in response to facilitate the detection of a plurality of gases. the dielectric is composed of rare earth fluoride, lanthanum fluoride, preferably. the ac impedance of the capacitor provides information on the type and concentration of the gas.