Scalable fabrication of highly sensitive flexible temperature sensors based on silver nanoparticles coated reduced graphene oxide nanocomposite thin films

We have demonstrated the scalability of RGO-Ag nanocomposite films based temperature sensor on kapton sheet for the flexible technology platform. The RGO nanosheets are known to have the tendency to form an agglomeration, which was removed by insertion of Ag nanoparticles to the RGO sheets. This resulted in the formation of nanocomposite material having an excellent conductivity suitable for temperature sensor applications. The electro thermal performance of the RGO-Ag nanocomposite sensing film was investigated using the Hot-Cold temperature setup. The sensor developed shows exceptional temperature sensing properties, with a promise for wide range of potential application possibilities. Till today the performance of temperature sensors are limited by the flexibility, lower sensitivity, non-linearity viz. Thermistors and Platinum based sensors viz. RTD & Pt 100 while linear are expensive. In contrast, the sensor developed in our present work shows negative temperature coefficient (NTC) of −1.64 × 10−3 Ω/Ω/K, sensitivity of 0.5553 Ω/K, with a non-linearity of about 1% and hysteresis close to 1%. The measured response time (470 m s) of this sensor is much faster than majority of commercially available temperature sensors with good repeatability and stability. The linearity of the developed sensor lends itself for simpler signal conditioning circuits without requiring linearization front end.