Substrate Dependent Analysis of Printed Sensors for Detection of Volatile Organic Compounds

This paper investigates all-printed gas sensors developed on different unconventional substrates and their effect of the detection of various volatile organic compounds (VOCs). An inkjet printing system is used to deposit the functional materials on PET (polyethylene terephthalate), paper and cotton fabric substrates. The different surface morphology and texture of the substrates are explored and used for developing the VOC sensors. Silver (Ag) nanoparticles based ink is used for printing the interdigital electrodes and the interconnect lines, whereas carbon black paste is used as the sensing layer. Sensors are tested against two different concentrations i.e. 4 and 22 ppm (parts per million) of three types of VOCs, i.e. acetone, ethanol and isopropanol. The comparative studies show a strong dependence of the VOCs detection on the type of substrates. Pros and cons of all the substrates, based on the processability, wearability, sensitivity and response times etc. are evaluated. This research presents significant contribution towards developing large area, low-cost and wearable VOC sensors, which are highly demanding in industrial and environmental monitoring as well as for potential analytes in biosensors to detect various chronic diseases.