Optical fiber sensors coated with GO/PANI nanocomposite integrating a microcontroller-based acquisition and processing system

An etched-tapered silica multimode optical fiber (ETMMF) sensing platform is reported as a sensor for ethanol detection with remote monitoring for industrial applications. The MMF is modified by chemical etching followed by the tapering process inside a part of the etched area to improve its sensitivity to the surroundings. The sensor is coated with graphene oxide (GO)/Polyaniline (PANI) nanocomposites as a sensing layer by the drop cast method. Ethanol is used with a concentration range of 0.1-40%. The light emitted will undergo some losses due to the GO/PANI absorbance increase. The optical response will be detected by the photodetector and converted to digital form using an analog to digital converter to display the measurement on a computer under the control of a microcontroller and PC. The developed system uses optical fiber to adapt to real-time remote monitoring applications over two way100 m. The sensor optical response, response and recovery times, repeatability, resolution limit, selectivity coefficient, and selectivity are investigated. The ETMMF sensor showed response and recovery times of 16 and 22 s, respectively, with - 2.43/vol% sensitivity. The ETMMF ethanol sensor exhibited a considerably fast response and is highly stable and reversible. Hence, it is a potentially excellent candidate for industrial applications and SCADA systems. The use of ETMMF as a sensing platform for aqueous detection, in general, and ethanol particularly, has yet to be explored.