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Combining high sensitivity with fast response and high resolution remains a critical challenge for flexible temperature sensors. The present study leverages the intrinsically high surface-to-volume ratio of nanocomposite fibers as well as the high mechanical properties of nanomaterials for achieving conformable temperature sensors with accurate and fast detection of temperature. To achieve this, nanocomposite films of electrospun polyvinylidene fluoride (PVDF) with embedded silver (Ag) nanoparticles were layered with multiwall carbon nanotubes (MWCNT). The sensor showed a negative temperature coefficient (NTC) with excellent sensitivity of À0.18%/ C and a quick response rate of 11 s. The sensor also exhibited low self-heating errors for an activation current of 1 mA and excellent anti-interference ability when tested for bending forces and wet environments. The nanocomposite fiber-based sensor can be used for real-time monitoring of human body temperature as confirmed by successful experiments. The present work lays the foundation for integrating the sensor further with a user interface to create a wearable temperature monitoring system for mobile healthcare.

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Nanocomposite films were prepared with polyvinyl alcohol (PVA) as a base matrix and ZnO, SiO2 nanoparticles as a filler material. SiO2 and ZnO nanoparticles were synthesized using sol-gel and co-precipitation methods, respectively. PVA-ZnO, PVA-SiO2, and PVA-ZnO-SiO2 hybrid nanocomposite films were prepared by a solution film casting method. The presence of ZnO and SiO2 nanoparticles within the films has been confirmed by structural and morphological analysis of the films. Water solubility, water absorption and tensile strength was evaluated for all the films produced. The addition of both types of nanoparticles in the PVA matrix led to a reduction in water absorption in addition to the water solubility capability of the material when compared to the pure PVA film. Addition of nanoparticles resulted in an increase in the tensile strength of the composite films compared to the pure PVA films by 14%, 23%, and 66% for the PVA-ZnO, PVA-SiO2, and PVA-ZnO-SiO2 films respectively. This work provides a simple route to tune the properties of PVA embedded with metal oxide nanoparticles for food packaging and medical applications.

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