Abstract:
In this study, Co-Zn ferrite, GQDs and nanocomposites of GQDs/ Co-Zn ferrite were
synthesized using the methods such as co-precipitation, pyrolysis and the ultrasonication
assisted method. Different Characterization techniques XRD, FTIR, FL, UV, SEM, EDS,
Impedance analyzer and VSM were acquired to investigate the structure, morphology, and
properties of the prepared materials. XRD patterns confirmed the successful phase formation
of GQDs, CoZnFe2O4 and nanocomposites. SEM and EDXS results revealed the existence of
GQDs on the CoZnFe2O4 surface. The FTIR spectrum shows the two vibration modes in
ferrites and the presence of oxygen functional group in GQDs.FL revealed the blue emission
of GQDs while UV data exhibit the p-p* and n-p* transition. Moreover, Impedance
Spectroscopy was used to study the Dielectric parameters, and impedance of the samples.
Dielectric constant of GQDs/ Co0.5Zn0.5Fe2O4 was 8.55x10^3 which is higher than the pure
Co0.5Zn0.5Fe2O4 because of the micro capacitors produced due to the conductive network
formed by the GQDs. The Cole plots show the two semicircle which revealed the contribution
from the grain and boundary regions. The VSM data revealed the superparamagnetic behaviour
of the samples. Furthermore, the Nanocomposite GQDs/ Co0.5Zn0.5Fe2O4 is a promising
candidate for the supercapacitor and MRI application.
