As
a new class of two-dimensional materials, the MXene family has
triggered attention because of its unique electrical and mechanical
properties. MXene’s excellent electrical conductivity and hydrophilicity
make it an ideal option for polymer nanocomposite fabrication. For
the first time, polymer nanocomposites of polyvinyl alcohol (PVA)/Ti3C2T
x
(MXene) were used
for charge storage applications in the X-band frequency range (8.2–12.4
GHz). By implementing solution casting and vacuum-assisted filtration
(VAF), flexible thin films with exceptional dielectric properties
(solution casting @ 10.0 wt % MXene: ε′ = 370.5 and tan
δ = 0.11 and VAF @ 10.0 wt % MXene: ε′ = 3166 and
tan δ = 0.09) were fabricated. The reported dielectric constants
in this study are among the highest values obtained in X-band frequency
with low dielectric losses. This outstanding performance originates
from the high electrical conductivity of synthesized Ti3C2T
x
MXene (σ ≈
1.4 ± 0.077 × 106 S/m; the highest reported value
for Ti3C2T
x
MXene
to date in the literature), great dispersion state, and the nacre-like
structure of the polymer nanocomposites. Combining the exceptional
properties of MXene with the effective nacre-like structure, PVA/MXene
nanocomposites can be used as a novel charge storage material, fulfilling
the requirements of flexible electronics and energy storage devices.