Development of Graphene Based Sensors for Human Physiological Monitoring and Vacuum Measurement

Abstract

Nanomaterials have emerged as a remarkable class of materials in recent years owing to their excellent electrical, chemical, and physical properties. The first two-dimensional (2D) material to be discovered, graphene, has been the torchbearer in this regard with its superlative properties and a strong impact on numerous technologies. Sensor technology is one such space where nanomaterials have brought an impressive facelift. A new genre of sensors was imperative in the biomedical field where the existing brittle and rigid wafer-based electronics have their limitations. The present talk describes my work accomplished in the synthesis of graphene and innovative device fabrication techniques, which has led to sensors that are highly sensitive, flexible, stretchable, and skin-conformal, notably preferred in biomedical sensing technology. These flexible wearable sensors see potential service in monitoring human physiological parameters, like heart rate, breathing rate, body temperature, body de-hydration, limb movement, tactile sensing, and so on. These sensors have a direct impact on the well-being of the masses, especially considering the current crisis in healthcare systems. Another area identified for possible improvement using nanomaterials is the vacuum sensing technology in industrial applications, which has not seen significant improvement over a long period of time. Vacuum technology has far-reaching utilization in areas like medical equipment, water treatment and petrochemical plants, food and beverages industry, space technology, semiconductor industry, thin-film technology, nuclear and defense requirements, and so forth. The limitations of available vacuum measurement devices such as narrow operating range, large form factor, expensive and need for cascaded gauges can be addressed using the developed vacuum sensor based on graphene nanocomposite. This talk summarizes the research carried out towards the design and development of graphene-based sensors targeting the above-described domains. The work includes a graphene supercapacitor model-based strain sensor with high noise immunity for biomedical applications. A multifunctional piezoresistive sensor with graphene nanosheets with a focus on commercially viable wearable devices has been developed for vital biomonitoring requirements. Further, graphene nanocomposite with gas chemisorption property has been explored for vacuum pressure measurement for a broader scope of applications. The developed sensor prototypes based on graphene nanomaterial have given a fresh perspective in the field of sensor technology.