Investigation of structural, morphology, and conduction mechanism of GO–Fe3O4–TiO2 composite material
Abstract
The graphene oxide composite (GO), iron oxide (Fe3O4), and titanium dioxide
(TiO2) were prepared by the sol–gel process. The surface of GO is coated with
TiO2 and Fe3O4 nanoparticles, and the composite contains 10.26% C, 23.70% O,
57.17% Ti, and 8.87% Fe. The formation of anatase TiO2 and magnetite Fe3O4 on
the surface of GO was detected by XRD and Raman analysis. The N2 adsorption–desorption isotherm and pore size distribution results showed the formation
of a mesoporous material with a specifc surface area of 233.3 m2
/g, a total pore
volume of 0.298 cm3
/g, and an average pore diameter of 7.7 nm. The GO–Fe3O4–
TiO2 composite’s dielectric characteristics were examined in the frequency and
temperature ranges of 0.1 Hz–5 MHz and 293–373 K, respectively. The Nyquist
plot suggests the non-Debye conduction behaviour, which may be related to the
distribution of relaxation times within the composite material. The contribution of
grains and grain boundaries to the total conductivity is confrmed by impedance
spectroscopy. Jonscher’s power law was used to examine AC conductivity graphs,
and the variation in the exponent “s” revealed that CBH models accurately characterize the conduction mechanism in the composite. The dielectric measurements
reveal Maxwell–Wagner polarization and a thermal-activated relaxation process.