Characterization, electrical and optical properties of PVA/MnO2 nanocomposite materials

In this research, various concentrations of manganese dioxide (MnO2) is composed by
polyvinyl alcohol (PVA) to forming PVA /MnO2 films. The XRD and SEM are
respectively demonstrated the structure and morphological characteristics of the films. The
XRD results show that the PVA/MnO2 films is fabricated successfully. The SEM results
demonstrate that MnO2 is dispersed evenly along the PVA polymeric chains. The
conductivity, impedance and energy density were measured via an LCR bridge with
frequency 102 to 106 Hz. There is an increase in dielectric from 64 for PVA to 95 for
PVA/0.06MnO2 at 105 Hz, and also the conductivity increases from 3.61x10-3 S/cm for
PVA to 5.33x10-3 S/cm for PVA/0.06MnO2. The optical characteristics of PVA and
PVA/MnO2 films were recorded by UV/Vis spectroscopy. The band gap reduced from
5.01 eV for PVA to 4.85, 4.71, 4.59 eV respectively for PVA/0.02MnO2, PVA/0.04MnO2,
and PVA/0.06MnO2. And the Urbach tail is modified from 1.72 eV for PVA to 3.12,
3.453, and 3.66 eV respectively. The results of the present work open the possibility for
applied in different devices as energy storage systems and optoelectronics