Two-Dimensional Fillers Induced Superior Electrostatic Energy Storage Performance in Trilayered Architecture Nanocomposites

Abstract

Dielectric capacitors with ultrahigh power densities and fast charging/discharging rates are of vital relevance in advanced electronic markets. Nevertheless, a tradeoff always exists between breakdown strength and polarization, which are two essential elements determining the energy storage density. Herein, a novel trilayered architecture composite film, which combines outer layers of two-dimensional (2D) BNNS/poly(vinylidene fluoride-cohexafluoropropylene) (P(VDF-HFP)) with high breakdown strength and an intermediate layer made of blended 2D MoS 2 nanosheets/P(VDF-HFP) with large polarization, is fabricated using the layer-by-layer casting method. The insulating BNNS with a wide band gap is able to largely alleviate the distortion of the local electric field, thereby suppressing the leakage current and effectively reducing the conductivity loss, while the 2D MoS 2 nanosheets act as microcapacitors in the polymer composites, thus significantly increasing the permittivity. A finite element simulation is carried out to further analyze the evolution process of electrical treeing in the experimental breakdown of the polymer nanocomposites. Consequently, the nanocomposites possess an excellent discharged energy density of 25.03 J/cm 3 accompanied with a high charging/discharging efficiency of 77.4% at 650 MV/m, which greatly exceeds those of most conventional single-layer films. In addition, the corresponding composites exhibit an outstanding reliability of energy storage performance under continuous cycling. The excellent performances of these polymer-based nanocomposite films could pave a way for widespread applications in advanced capacitors.

Novel inorganic fillers of 1D hydroxyapatite nanowires induced superior energy storage performances of P(VDF–HFP)-based composite films

“…12,36,[51][52][53][54][55][56][57][58] The nanocomposite lm of P(VDF-HFP)/HAP@Al 2 O 3 NWs-4 exhibits the highest U N ($289%) among these classical nanocomposite lms. In addition, U d and E b of several composite lms with nanollers (including low dielectric constant, 15,25,59 high dielectric constant 15,[60][61][62][63][64][65] and core-shell structure 12,20,66 ) reported in the past are illustrated in Fig. 3d.…”

“…23,24 This is because the large-aspect-ratio 1D nanollers not only signicantly improve K, but also form an ordered dispersion center that could hinder the development of electrical trees to promote E b . [25][26][27] For example, Wang et al 28 revealed that 1D BT NFs loaded into a poly(vinylidene uoride) (PVDF) matrix exhibited larger K (11.03 vs. 14.69 at 1 kHz), better E b (300 vs. 370 MV m −1 ) and higher U d (4.86 vs. 8.78 J cm −3 ) than those of 0D BT NPs.…”

Polyimide-Based Composite Films with Largely Enhanced Energy Storage Performances toward High-Temperature Electrostatic Capacitor Applications

“…To further investigate the difference in conduction activation energy between pure PI and 5BN/PI-S nanocomposites, the activation energy ( A c ) could be fitted by the Arrhenius relation − where σ­( T ), σ 0 , T , e , and K b represent the volume conductivity, prefactor, temperature, carrier charge, and Boltzmann constant, respectively. As illustrated in Figure a, the A c for PI and 5BN/PI-S nanocomposites is fitted by the volumetric conductivity measured at different temperatures.…”

Flexible cyanoethyl cellulose-based nanocomposites with superior energy storage capability

“…10,28,34,35 For instance, more recently, it has been indicated that the introduction of 2D BNNs and MoS 2 into the PVDF-HFP matrix formed trilayered architecture composite films that could simultaneously improve polarization and breakdown strength, thus exhibit a prominent discharged energy density of 25.03 J cm −3 with a high efficiency of 77.4% at an electric field of 650 MV m −1 . 10…”