Poly(vinylidene fluoride)/NH₂-Treated Graphene Nanodot/Reduced Graphene Oxide Nanocomposites with Enhanced Dielectric Performance for Ultrahigh Energy Density Capacitor

Abstract

This work describes a ternary nanocomposite system, composed of poly(vinylidene fluoride) (PVDF), NH2-treated graphene nanodots (GNDs), and reduced graphene oxides (RGOs), for use in high energy density capacitor. When the RGO sheets were added to PVDF matrix, the β-phase content of PVDF became higher than that of the pristine PVDF. The surface-treatment of GNDs with an ethylenediamine can promote the hydrogen bonding interactions between the GNDs and PVDF, which promote the formation of β-phase PVDF. This finding could be extended to combine the advantages of both RGO and NH2-treated GND for developing an effective and reliable means of preparing PVDF/NH2-treated GND/RGO nanocomposite. Relatively small amounts of NH2-treated GND/RGO cofillers (10 vol %) could make a great impact on the α → β phase transformation, dielectric, and ferroelectric properties of the ternary nanocomposite. The resulting PVDF/NH2-treated GND/RGO nanocomposite exhibited higher dielectric constant (ε' ≈ 60.6) and larger energy density (U(e) ≈ 14.1 J cm(-3)) compared with the pristine PVDF (ε' ≈ 11.6 and U(e) ≈ 1.8 J cm(-3)).

High-k Polymer Nanocomposites for Energy Storage Applications

“…Graphene oxide (GO) can be easily dispersed in the aqueous solution and the electrical properties can be optimized by using various thermal and chemical approaches such as partial reduction. Thus, the GO/polymer nanocomposites can prove an efficient system for high dielectric applications [49,50]. Recently, attention has been given to the carbon nanotubes (CNTs), a crystalline form of carbon because of their unique physical and mechanical properties.…”

Ni/Al2O3/epoxy high-k composites with ultralow nickel content towards high-performance dielectric applications

“…As we know, the dielectric properties of a composite will undergo signicant changes near its percolation threshold, [8][9][10][11] and numerous researches have conrmed that percolative composites are promising candidates for high-k materials with outstanding dielectric properties, such as tunable high permittivity, high dielectric strength, low loss, etc. Therefore, various strategies have been developed to obtain high-k according to percolation theory in composite materials, such as ferroelectric/polymer composites, [12][13][14] binary or ternary metal (or carbon)/polymer composites, [15][16][17] metal (or carbon)/ ceramic composites, etc. [18][19][20][21] In these composites, a certain volume fraction (lower than but still near the percolation threshold) of metal, carbon or ferroelectric powders should be dispersed into the matrix to achieve excellent dielectric performance.…”

High Energy Density in Poly(Vinylidene Fluoride‐Chlorotrifluoroethylene) Nanocomposite with Oriented Graphene Exfoliated with Assistance of Fluoro Hyperbranched Copolymer

“…The electrical density of 0.67 J cm −3 at 50 MV m −1 was obtained in 1.5 vol% rGO/PVDF nanocomposite, which was attributed to the combination of lowering of electrical contrast in components and decrease of localized charge carriers . The dielectric constant of 60.6 at 100 Hz and energy‐harvesting density of 14.1 J cm −3 at 400 MV m −1 were obtained in 10 vol% PVDF composite embedded with NH 2 ‐treated graphene nanodot and rGO as co‐fillers . The polyaniline functionalized graphene was added into the PVDF matrix, and ε ′ = 264 with a dielectric loss of 1.1 at 100 Hz was obtained in 5 wt% composite, which was attributed to the synergistic effect under uniform dispersion .…”