Abstract
Polyvinyl alcohol/yttrium oxide (PVA/Y(2)O(3)) nanocomposite films with five different weight ratios of PVA and Y(2)O(3) nanoparticles (NPs) were prepared using a simple solution casting method. The prepared polymer nanocomposite (PNC) films were examined using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). FTIR spectra exhibited a strong interaction between the PVA matrix and Y(2)O(3) NPs. SEM results indicated that Y(2)O(3) NPs were properly dispersed in the PVA matrix. The thermal stability of the PVA/Y(2)O(3) nanocomposite films was found to be dependent on Y(2)O(3) NP loading (wt%) in the nanocomposite films. Furthermore, chemiresistive gas sensing properties of the PVA/Y(2)O(3) nanocomposite films were evaluated and the sensing parameters including sensing response, operating temperature, selectivity, stability, response/recovery time, and repeatability were systematically investigated based on the change in electrical resistance of the nanocomposite film in the presence of carbon dioxide (CO(2)) gas. The maximum sensing response (S) of 92.72% at a concentration of 100 ppm under an optimized operating temperature of 100 °C with a fast response/recovery time of ∼15/11 s towards CO(2) gas detection was observed for the PVA/Y(2)O(3) nanocomposite film with 5 wt% loading of Y(2)O(3) NPs in the PVA matrix. The finding in this work suggest that Y(2)O(3) NPs are sufficiently fast as a CO(2) gas sensing material at a relatively low operating temperature. Moreover, the key role of the Y(2)O(3) NPs in modulating the electrical and gas sensing properties of the PVA matrix is discussed here.