Graphene oxide/polyaniline-based microwave split-ring resonator: A versatile platform towards ammonia sensing

• Published in: Journal of hazardous materials Vol. 418; p. 126283
• Main Authors: Javadian-Saraf, Aida, Hosseini, Ehsan, Wiltshire, Benjamin Daniel, Zarifi, Mohammad H., Arjmand, Mohammad
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.09.2021
• Subjects: Ammonia; Graphene oxide; Polyaniline; Sensor; Split-ring resonator; Split-ring resonator; Ammonia; Graphene oxide; Polyaniline; Sensor
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.126283

Ammonia gas sensors have always received significant attention as robust platforms for emission control, food safety, and monitoring human exhaled breath for the early diagnosis of diseases such as dysfunction of the kidney and liver. This study explores the development of a microwave-based split-ring resonator (SRR) sensor with enhanced sensitivity to detect ammonia gas at low concentrations. The sensor is based on a nanocomposite fabricated by incorporating 10 wt% of graphene oxide (GO) into polyaniline (PANI) via the in-situ polymerization of aniline monomers over the surface of the GO sheets. The addition of GO to PANI results in a high sensitivity of 0.038 dB ppm−1 for low concentrations (1–25 ppm) and 0.0045 dB ppm−1 for high concentrations (> 25 ppm) of ammonia gas, in a 150–400 s time interval at room temperature. The prepared sensor can selectively sense ammonia gas in the presence of other higher concentrations of hazardous gases and a wide range of relative humidity levels (15–90%). The response signal is repeatable after 30 days with less than 0.32% deviation. The developed low-cost and robust sensor has the potential to monitor ammonia gas in various applications, including medical, environmental, food, and agricultural sectors. [Display omitted] •Addition of GO to PANI as a template and dopant altered the conductivity of PANI.•Remarkable sensitivity of 0.038 dB ppm−1 for concentrations as low as 1 ppm.•Fast detection of ammonia gas as low as 150 s at room temperature.•Detection of ammonia gas within a wide range of 15–90% relative humidity.•Highly selective in sensing ammonia gas in the presence of other hazardous gases.