Infrared Light Annealing Effect on Pressure Sensor Fabrication Using Graphene/Polyvinylidene Fluoride Nanocomposite

This paper reports the designing and testing, as well as the processing and testing, of a flexible piezoresistive sensor for pressure-sensing applications, utilizing a composite film of graphene/polyvinylidene fluoride (Gr/PVDF). Graphene serves as the conductive matrix, while PVDF acts as both the binder and a flexible polymer matrix. The composite film was fabricated using the solution casting technique on a flexible polyethylene substrate. We investigated the impact of post-infrared annealing on the pressure response of the Gr/PVDF films. The experimental results indicated that the films IR-annealed for 2 min exhibited improved pressure sensitivity compared with the as-deposited films. The stability and durability of the sensors were assessed through the application of pressure over more than 1000 cycles. The mechanical properties of the films were examined using a universal tensile testing machine (UTM) for scenarios both with and without infrared light annealing. Raman spectroscopy was employed to analyze the quality and characteristics of the prepared nanocomposites. This study enhances our understanding of the interplay between the Gr/PVDF composite, the IR annealing effect, and the hysteresis effect in the pressure-sensing mechanism, thereby improving the piezoresistance of the Gr/PVDF nanocomposite through the infrared annealing process.