2D‐Nanofiller‐Based Polymer Nanocomposites for Capacitive Energy Storage Applications

Abstract

High-energy-density storage devices play a major role in modern electronics from traditional lithium-ion batteries to supercapacitors for a variety of applications from rechargeable devices to advanced military equipment. Despite the mass adoption of polymer capacitors, their application is limited by their low energy densities and low-temperature tolerance. Polymer nanocomposites based on 2D nanomaterials have superior capacitive energy densities, higher thermal stabilities, and higher mechanical strength as compared to the pristine polymers and nanocomposites based on 0D or 1D nanomaterials, thus making them ideal for high-energy-density dielectric energy storage applications. Here, the recent advances in 2D-nanomaterial-based nanocomposites and their implications for energy storage applications are reviewed. Nanocomposites based on conducting 2D nanofillers such as graphene, reduced graphene oxide, MXenes, semiconducting 2D nanofillers including transition metal dichalcogenides such as MoS 2 , dielectric 2D nanofillers including hBN, Mica, Al 2 O 3 , TiO 2 , Ca 2 Nb 3 O 10 and MMT, and their effects on permittivity, dielectric strength, capacitive energy density, efficiency, thermal stability, and the mechanical strength, are discussed. Also, the theory and machine-learning-guided design of polymer 2D nanomaterial composites is learnt and the challenges and opportunities for developing ultrahigh-capacitive-energy-density devices based on these nanofiller polymer composites are presented.

Energy Storage Performance of Polymer-Based Dielectric Composites with Two-Dimensional Fillers

“…One of the challenges associated with utilizing CNTs as fillers is the tendency for them to form agglomerates inside the polymer matrix. Modification and functionalization are widely utilized techniques for enhancing the dispersion of CNTs within host polymers [53,66]. Recently, researchers proposed 2D conducting fillers, including graphene, graphene oxide (GO), reduced graphene oxide (RGO), and MXene, to achieve a uniform dispersion of conductive fillers in the dielectric matrix to maximize the composite's electrical properties [67], which will be discussed in Sections 4.4 and 4.6.…”

Self-Cross-Linking of MXene-Intercalated Graphene Oxide Membranes with Antiswelling Properties for Dye and Salt Rejection

“…MXenes are two-dimensional (2D) metallic materials composed of transition metal carbides and nitrides. ,, The MXene family involves the addition of various hydrophilic Ti 3 C 2 T x functional groups (T corresponds to hydroxyl, oxygen, or fluorine groups), and this material has proven to be chemically versatile and useful in numerous previous applications . In particular, there are many applications in the areas of energy storage, electromagnetic interference shielding, , membrane-based separation, and other areas, and these materials continue to be of great interest for many applications. , MXene exhibits superior resistance to swelling compared to GO. When MXene, specifically Ti 3 C 2 T x , is combined with graphene, it readily integrates into the graphene sheet layers.…”

Ultrahigh Capacitive Energy Density in Stratified 2D Nanofiller-Based Polymer Dielectric Films

“…Embedding nanofillers in a polymer matrix can enhance their permittivity, but the dielectric strength is limited due to a random distribution of the fillers, resulting in low to moderate energy densities. Furthermore, the nanoparticle aggregation and air voids in these nanocomposites decrease dielectric strength, thereby negatively impacting the energy stored in the dielectrics. − Recently, 2D nanofiller-based polymer nanocomposites ,, have shown potential for use as relatively higher energy density energy storage devices such as Ca 2 Nb 3 O 10 based nanosheets in poly­(vinylidene fluoride) (PVDF) matrix have shown energy densities of 36 J/cm 3 with efficiencies of 60% . However, the energy densities and efficiencies of these nanocomposites remain low for practical application .…”