SINGLE-ELECTRODE GAS SENSOR BASED ON OXIDISED TITANIUM, METHOD FOR PRODUCTION THEREOF, SENSOR DEVICE AND MULTI-SENSOR LINE BASED THEREON

摘要

The invention relates to the field of gas analysis, namely to sensor devices for gas and gas mixture analysis and method of production thereof. Described is a method of producing a single-electrode gas sensor based on titanium wire, which is oxidised by anodizing in an electrochemical cell, to form mesoporous oxide layer consisting of radially oriented ordered TiO₂ nanotubes with wall thickness of up to 20 nm and inner diameter of up to 150 nm. Said method enables to obtain a single-electrode gas sensor, in which the heating and measuring electrodes used are a titanium wire with diameter of 50-250 m, and a catalytic layer is a mesoporous oxide layer consisting of TiO₂ nanotubes. This single-electrode sensor has response to organic pairs in the form of change of resistance at passage of operating current in the range of 80-200 mA. For use in sensor devices, the single-electrode gas sensor is connected either directly to a current source, or connected to a voltage source through a divider, or connected to a bridge circuit, where a compensating element is either a passive resistor having resistance close in value to resistance of oxidised titanium wire, or other single-electrode sensor based on oxidized titanium wire with different diameter of metal titanium. For selective analysis of gases based on a set of single-electrode gas sensors, the number of which is not less than three, a multisensor line is composed, vector signal of which enables to distinguish the effect of single-type vapors of alcohols, for example isopropanol and ethanol. The technical result of the invention consists in creating a new type of a single-electrode gas sensor with low cost, as well as sensor devices based on such a sensor and multisensor lines.