E-textile based wearable thermometer from WS 2 -quantum dots

Abstract We report here the successful operation of WS 2 -QD/RGO hybrid temperature sensor, which performs instant measurement like thermometer in a wide temperature range: 77–398 K, in both static- and instant mode. All this was possible by embedding WS 2 -QDs on electrically conducting RGO layer, synthesized on cotton textile fabric. The device is simple, scalable, flexible and cost-effective. Successful trial to monitor human body temperature is conducted with fast response- and recovery time ∼0.60 and 11.3 s with an exceptional resolution ∼0.06 K. Crucial parameters such as temperature coefficient of resistance (TCR) and thermal hysteresis ( H th ) were theoretically analyzed to understand the intricate mechanism behind the working of a temperature sensor; temperature sensing data at both high- and low temperatures are outstanding as well as competitive. To mention, a few of these parameters are found comparable and even superior to some of the devices as reported. This sensor device proved its flexibility and stability under various in situ mechanical deformation tests, showing its promising potential for future generation wearable health monitoring devices. To the best of our knowledge, this is the first report on WS 2 in general, and WS 2 -QDs, in specific, based temperature sensing device and its operational demonstration as of now.