Polyvinyl chloride-reduced graphene oxide based chemiresistive sensor for sensitive detection of ammonia

In this study, we present the innovative development of sensitive chemiresistive sensor utilizing a composite material composed of polyvinyl chloride (PVC) and reduced graphene oxide (rGO) for the highly responsive detection of ammonia (NH3) at ambient conditions. Graphene oxide (GO) was meticulously synthesized employing an enhanced version of Hummer’s method, and subsequently, rGO was prepared via thermal reduction from GO. The PVC/rGO composite was synthesized using a precise chemical pathway. The synthesized material was comprehensively characterized using advanced techniques including X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy, Raman spectroscopy, atomic force microscopy (AFM), and I–V measurements, unveiling its structural, spectroscopic, morphological, and electrical attributes. The chemiresistive sensor was fabricated through the meticulous drop-casting of PVC/rGO composite onto an economical Cu interdigitated electrode (IDE) pattern. Remarkably, this PVC/rGO-based chemiresistive sensor exhibited superior performance in detecting corrosive NH3. The sensor demonstrated an exceptional response time of 46 s and a recovery time of 88 s, coupled with an impressively low detection limit of 1 ppm, surpassing the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL). Notably, this sensor displayed a remarkable selectivity towards NH3 at ambient conditions, outperforming its response to other gases. Furthermore, the sensor exhibited outstanding reproducibility, repeatability, linearity, sensitivity, and stability in its response to NH3. This research showcases a groundbreaking advancement in the field of gas sensing technology, offering a highly sensitive and selective chemiresistive sensor for NH3 detection at room temperature (RT). The synergistic combination of PVC and rGO in the composite material, along with the precise fabrication techniques employed, has resulted in a sensor with unparalleled performance characteristics, promising significant implications for real-world applications demanding precise and reliable gas detection capabilities.