Nanocomposites comprising PVA/CMC matrix and CNTs/Fe2O3 nanohybrid: A comparative investigation of structural, optical, electrical, and dielectric properties as an application in advanced electrochemical and optoelectronic devices

Abstract

This work addresses the fabrication of innovative flexible polymer nanocomposite films for electrochemical products made of poly (vinyl alcohol) (PVA), carboxymethyl cellulose (CMC), multi-walled carbon nanotubes (CNTs), and hematite (α-Fe2O3) nanoparticles (NPs) as nanohybrid. The PVA/CMC-CNTs/Fe2O3 nanocomposite films were characterized using various approaches. The PVA/CMC blend polymer matrix shows significant improvements in terms of amorphous nature with the CNTs/Fe2O3 nanofiller content, resulting in an exceedingly flexible polymer backbone and with higher ionic conductivity of the PVA/CMC-CNTs/Fe2O3 nanocomposites films, as reported by the XRD examination. The nanoparticle surfaces and the blend matrix exhibit a significant interaction, as seen by the FTIR spectra. To learn more about how CNTs/Fe2O3 NPs affect the optical characteristics of the PVA/CMC, its optical characteristics were examined. The absorption edge appeared to migrate towards lower photon energy sides upon the addition of CNTs/Fe2O3 NPs to the PVA/CMC matrix. The Eg (direct and indirect) of pure PVA/CMC was considerably decreased from 5.12 to 3.55 eV and 4.23 to 3.01 eV respectively by adding 3.5 wt% of CNTs/Fe2O3 NPs. The results proved the influence of the nanofiller on the host polymer's decreased band gap energy. The blend nanocomposite had a substantially higher AC conductivity compared with the blend, and the PVA/CMC-3.5%CNTs/Fe2O3 nanocomposite had the highest electrical conductivity. It was discovered that while the dielectric loss and dielectric constant increased with the high content of nanoparticles, they reduced with increasing frequency. These findings demonstrated that the produced films had undergone substantial changes, which allows for the use of flexible films made of PVA/CMC-CNTs/Fe2O3 in a variety of electrochemical and optoelectronic applications.