Heat Treatment of Nanofibrous Carbon for NO2 Room Temperature Gas Sensor

The high-temperature treatment of nanofibrous carbon, carried out at 2600°C (in the absence of air), is investigated. The obtained samples are studied using thermal analysis, transmission electron microscopy, and Raman spectroscopy. The carbon samples are tested as active material in gas sensors for the detection of nitrogen dioxide. It is shown for the first time that heat treatment of nanofibrous carbon leads to a sharp increase in sensitivity by ~5 times at 1 ppm NO2 relative to the initial sample. Unlike other treatment methods, heating to high temperatures in the absence of air leads to an increase in the degree of graphitization, formation of the well-ordered structure of nanofibers, the removal of catalyst residues, and an increase in the functional characteristics of the sensors.