Millions of people across the globe are severely afflicted because of water potability issues, and to proffer a solution to this crisis, efficient and cost-effective desalination techniques are necessitated. Membranes, in particular Graphene-derived membranes, have emerged as a potential answer to this grave problem because of their tunable ionic and molecular sieving capability, thin structure, and customizable microstructure. Among graphene-derived membranes, Graphene Oxide membranes have been the most promising, given the replete presence of oxygen-containing functional groups on its surface. However, the prospects of commercial applicability of these membranes are currently plagued by uneven stacking, crossflow delamination, flawed pores, screening and pH effects, and horizontal defects in the membrane. In addition, due to the selectivity–permeability trade-off that commonly exists in all membranes, the separation efficiency is negatively influenced. This review, while studying these challenges, aims to outline the most recent ground-breaking developments in graphene-based membrane technology, encompassing their separation mechanism, selectivity, adjustable mechanical characteristics, and uses. Additionally, we have covered in detail how several process variables such as temperature, total oxygen concentration, and functional groups affect the effectiveness of membrane separation with the focal point tilted toward studying the currently used intercalation techniques and effective nanomaterial graphene oxide membranes for water desalination

This review provides a detailed overview of the latest developments using nanoscale strategies in the field of polymeric and polymer nanocomposite materials for emerging dielectric capacitor-based energy storage applications. Among the various energy storage devices, solid-state dielectric capacitors possess the advantage of high-power density which makes them highly attractive for pulsed power applications. Polymers are particularly suitable for dielectric energy storage applications because of their high breakdown strength, low dielectric loss, formability, self-healing capability, flexibility, solvent processability, and graceful breakdown failure. Strategies to enhance the dielectric breakdown strength of polymeric dielectric capacitors are emphasized in this review. General background on breakdown mechanism, breakdown characteristics, and factors influencing polymer dielectrics breakdown are introduced. Given that polymers have low permittivity, strategies to substantially enhance dipole mobility and hence the permittivity, are highlighted. We discuss strategies to address permittivity contrast between nanofillers and the polymer matrix including the potential for developing gradient permittivity structured nanofillers. To improve the compatibility of nanofiller with polymer and minimize nanofiller aggregation, different routes to surface functionalize nanoparticles are presented. An outlook and future perspectives section are provided for the design of high energy density polymer film capacitors.

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 MoS₂, dielectric 2D nanofillers including hBN, Mica, Al₂O₃, TiO₂, Ca₂Nb₃O₁₀ 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.

Designing high energy density dielectric capacitors for advanced energy storage systems needs nanocomposite-based dielectric materials, which can utilize the properties of both inorganic and polymeric materials. Polymer-grafted nanoparticle (PGNP)-based nanocomposites alleviate the problems of poor nanocomposite properties by providing synergistic control over nanoparticle and polymer properties. Here, we synthesize "core-shell" barium titanate-poly(methyl methacrylate) (BaTiO₃-PMMA) grafted PGNPs using surface-initiated atom transfer polymerization (SI-ATRP) with variable grafting densities of (0.303 to 0.929) chains/nm² and high molecular masses (97700 g/mL to 130000 g/mol) and observe that low grafted density and high molecular mass based PGNP show high permittivity, high dielectric strength, and hence higher energy densities (≈ 5.2 J/cm³) as compared to the higher grafted density PGNPs, presumably due to their "star-polymer"-like conformations with higher chain-end densities that are known to enhance breakdown. Nonetheless, these energy densities are an order of magnitude higher than their nanocomposite blend counterparts. We expect that these PGNPs can be readily used as commercial dielectric capacitors, and these findings can serve as guiding principles for developing tunable high energy density energy storage devices using PGNP systems.

Dielectric capacitors are critical components in electronics and energy storage devices. The polymer-based dielectric capacitors have the advantages of device flexibility, fast charge-discharge rates, low loss, and graceful failure. Elevating the use of polymeric dielectric capacitors for advanced energy applications such as electric vehicles (EVs), however, requires significant enhancement of their energy densities. Here, we report a polymer thin film heterostructure-based capacitor of poly(vinylidene fluoride)/poly(methyl methacrylate) with stratified 2D nanofillers (Mica or h-BN nanosheets) (PVDF/PMMA-2D fillers/PVDF), that shows enhanced permittivity, high dielectric strength, and an ultrahigh energy density of ≈75 J/cm³ with efficiency over 79%. Density functional theory calculations verify the observed permittivity enhancement. This approach of using oriented 2D nanofillers-based polymer heterostructure composites is expected to be versatile for designing high energy density thin film polymeric dielectric capacitors for myriads of applications.

MXenes, a novel class of two‐dimensional (2D) transition metal carbides, carbonitrides, and nitrides, have gained significant attention in biomedicine. They are synthesized via two main approaches: top‐down etching of MAX (here, M represents an early transition metal, A represents an element belonging to the A‐group, and X represents N or C) phase precursors and bottom‐up chemical reduction of metal oxides. While the MAX phase method requires high temperatures, influencing morphology and posing safety concerns, alternative non‐MAX synthesis routes are emerging. Due to their unique physical and chemical properties, MXene‐based composites hold great promise in regenerative medicine, biosensing, and cancer therapy. However, challenges related to their stability, controlled drug release, and biodegradability remain. This review explores advancements in MXene synthesis, emphasizing non‐MAX phase fabrication and biomedical applications. Notably, MXene‐based composites have shown remarkable potential in cancer treatment, particularly in photothermal and photodynamic therapy. Their mechanisms, advantages, and limitations are discussed, along with future prospects and challenges in clinical translation. The development of MXene composites offers new avenues for innovative cancer therapies, paving the way for improved treatment strategies.