from the conferences organized by TANGER Ltd.
Currently, great emphasis is placed on air quality and the presence of pollutants, whether on toxic substances (NH3 or CO), substances that reduce the quality of life (CO2) or chemical vapors from industries (acetone or ethanol). Attention is therefore focused on new gas-sensing materials enabling detection even at low (up to room) temperatures with sufficient response and short reaction time.Here, we investigate the suitability of hydrogen-terminated nanocrystalline diamond (H-NCD) films and their heterostructures with molybdenum disulfide (MoS2), graphene oxide (GO), reduced GO (rGO), thiolfunctionalized GO (SH-GO), or gold nanoparticles (Au NPs) for gas sensing applications. Electrical properties are measured for oxidizing gas NO2, reducing gas NH3, and chemical vapor of ethanol (C2H5OH), and at temperatures varied from room temperature to 125 °C. All tested gases were used with a concentration of up to 100 ppm. Synthetic air is used as the flushing gas. The measured parameters of the tested sensors are compared, both with each other and with commercial sensors, and subsequently evaluated. In contrast to the individual forms of employed materials with limited response to the exposed gases, the HNCD heterostructures revealed better sensing properties. In particular, the Au NPs/H-NCD heterostructures revealed a higher response at 125 °C in contrast to H-NCD, MoS2/H-NCD had quite good response even at room temperature and GO/H-NCD revealed high sensitivity to chemical vapor, which further improved for the SH-GO/HNCD.
Keywords: Gas sensors, nanocrystalline diamond, heterostructures, air quality monitoring© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.