Integration of Highly Sensitive Oxygenated Graphene With Aluminum Micro-Interdigitated Electrode Array Based Molecular Sensor for Detection of Aqueous Fluoride Anions

Soni, Mahesh and Arora, Tarun and Khosla, Robin and Kumar, Pawan and Soni, Ajay and Sharma, Satinder K. (2016) Integration of Highly Sensitive Oxygenated Graphene With Aluminum Micro-Interdigitated Electrode Array Based Molecular Sensor for Detection of Aqueous Fluoride Anions. IEEE Sensors Journal, 16 (6). pp. 1524-1531. ISSN 1530-437X

Abstract

High sensitivity and reliability of graphene oxide (GO) integrated with aluminum (Al) micro-interdigitated electrodes (μ-IDEs) patterned on p-Si for the detection of aqueous fluoride anion (F - ) is demonstrated. The strong molecular interaction, hydrogen bonding, and ionic conduction between the oxygen containing functional groups (epoxy (1, 2-ether), hydroxyl, carbonyl, and carboxyl) onto GO and F - are investigated by electrical and optical techniques. The GO/Al (μ-IDEs)/p-Si sensor system shows ~82% increase in the sensing signal for 0.1 ppm GO + F - solution with respect to GO. The response of the sensor for 1, 10, 100, and 1000 ppm of GO + F - solution shows almost 220, 415, 500, and 305 times increase in sensing signal with respect to GO. The significant enhancement in sensor response at lower concentration (0.1-100 ppm) of F - is observed. However, at high concentration (1000 ppm) of F - , the interlayer swelling and the expansion of GO dominate and result the reduction in sensing response of GO/Al (μ-IDEs)/p-Si sensor. The Fourier transform infrared spectroscopy (FT-IR) spectra show the decrease in -OH, C-O-C, and CLO absorption peaks of GO with an increasing aqueous F - concentration, supporting the reduction in sensing response at 1000 ppm. The response of GO/Al (μ-IDEs)/p-Si sensor is favorable for use in graphene-based electronics sensors.