PVDF/ZnO hybrid nanocomposite applied as a resistive humidity sensor

Abstract

Polyvinyledene fluoride (PVDF), an aliphatic polymer with massive hydrophobic groups, has been developed as humidity sensitive material (hydrophilic) using an additive of ZnO nanoparticles as resistant transduction layers, an PVDF/ZnO nanocomposite bas been prepared as humidity sensor through a simple hydrothermal approach. PVDF/ZnO nanocomposite have been fabricated by spin coating method and characterized by XRD, FE-SEM, TEM, BET, UV-Vis spectra and PL spectra. Owing to its 2D replicated structure with rod-like nanocomposite, the PVDF/ZnO provide more water molecules adsorption and desorption across the humidity sensor surface compare than pure ZnO nanoparticles. The humidity sensing properties was established by using saturated salt solutions and the relative humidity range of 5-95% were achieved at 35°C. The experimental results confirmed that the sensitivity factor (Sf) of PVDF/ZnO nanocomposite humidity sensor exhibit 3 order of magnitude variation than that of pure PVDF and good linearity compare than pure ZnO nanoparticles. The response and recovery times of the nanocomposite based humidity sensor are to be 30 s and 51 s, respectively. The performance of PVDF/ZnO nanocomposite sensor can be improved by PVDF modifier on ZnO nanoparticles, because the PVDF/ZnO nanocomposite have more surface oxygen vacancy defects was synthesized by hydrothermal method. The experimental analysis indicates that the enhanced humidity sensitivity was probably due to BET surface area and provides more water adsorption sites in hybrid nanocomposite. These results open the door for a new idea for high performance and promising 2D nanocomposite materials in the development of sensitive RH% sensor for potential in the manufacture of humidity sensors.