A calibrated graphene-based chemi-sensor for sub parts-per-million NO2 detection operating at room temperature

• Published in: Applied physics letters Vol. 104; no. 18
• Main Authors: Ricciardella, F., Massera, E., Polichetti, T., Miglietta, M. L., Di Francia, G.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 05-05-2014
• Subjects: Aluminum oxide; Applied physics; Calibration; Gold; Graphene; Nitrogen dioxide; Organic chemistry; Recovery time; Relative humidity; Room temperature; Sensors; Substrates
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4875557

Here, we present a room temperature operating chemi-sensor based on a graphene film that shows sensitivity to NO2 up to a 50 parts-per-billion (ppb) with extremely limited interference from relative humidity and can be also calibrated in a sub-parts-per-million (ppm) range with a response and recovery time of few seconds. The device has been fabricated using as active material, a solution of graphene nanosheets suspended in N-methyl-pyrrolidone drop casted on an alumina substrate with gold interdigitated electrodes. The derivative of the device response is found to be univocally correlated to NO2 concentrations from 100 ppb up to 1000 ppb and the sensor can therefore be calibrated in this same range.