Screen Printed Temperature Sensor Using Novel Kish Graphite/Reduced Graphene Oxide Conductive Ink for Wearable Applications

This paper introduces a novel screen-printed temperature sensor with a conductive ink made of reduced Graphene Oxide (GO) and Kish Graphite (rGO/KG). KG, an industrial waste, was recovered from the purification of dust obtained from the blast furnace area in the steel manufacturing unit. Further, rGO/KG conductive inks were prepared, and they were screen printed on Polyethylene Terephthalate (PET) substrate to fabricate the flexible temperature sensor. The temperature sensor's performance has been evaluated, and the results show superior sensitivity compared to commercial sensors. Three different rGO/KG composite screen printable inks were prepared, with varying ratios of rGO: KG fine powders (1:1, 1:2, and 1:4). The sensor with rGO: KG ratio (1:2) displayed a better sensitivity of 59.8 % /°C on par with sensor made with commercial ink. Bending tests confirm the sensor maintains its characteristics, demonstrating good mechanical stability. Hence, this flexible, screen-printed temperature sensor, using the rGO/KG ink, is suitable for production and implementation on a large scale.