An innovative strategy was designed to improve the energy storage properties of Bi_0.5Na_0.5TiO₃–SrTiO₃ (BNT–ST)-based relaxor ferroelectric ceramics, in which the bismuth layer-structured relaxor BaBi₂Nb₂O₉ (BBN) was adopted as the modifier.

An ABS film, which exhibits a high gravimetric energy density of 6.3 J g⁻¹ with satisfactory efficiency, excellent thermal stability, and cycling reliability at elevated temperatures, is a promising candidate for high power energy storage capacitors.

Dielectric capacitors have garnered significant attention in recent decades for their wide range of uses in contemporary electronic and electrical power systems. The integration of a high breakdown field polymer matrix with various types of fillers in dielectric polymer nanocomposites has attracted significant attention from both academic and commercial sectors. The energy storage performance is influenced by various essential factors, such as the choice of the polymer matrix, the filler type, the filler morphologies, the interfacial engineering, and the composite structure. However, their application is limited by their large amount of filler content, low energy densities, and low-temperature tolerance. Very recently, the utilization of two-dimensional (2D) materials has become prevalent across several disciplines due to their exceptional thermal, electrical, and mechanical characteristics. Compared with zero-dimensional (0D) and one-dimensional (1D) fillers, two-dimensional fillers are more effective in enhancing the dielectric and energy storage properties of polymer-based composites. The present review provides a comprehensive overview of 2D filler-based composites, encompassing a wide range of materials such as ceramics, metal oxides, carbon compounds, MXenes, clays, boron nitride, and others. In a general sense, the incorporation of 2D fillers into polymer nanocomposite dielectrics can result in a significant enhancement in the energy storage capability, even at low filler concentrations. The current challenges and future perspectives are also discussed.

In this study, novel lead-free Sr_1.75Ca_0.25NaNb₅O₁₅ tungsten bronze ceramics were designed for potential energy storage applications. A remarkable energy storage density (∼3.23 J cm⁻³) along with a high energy storage efficiency (∼88.2%) was obtained simultaneously at an applied electric field of 290 kV cm⁻¹. Moreover, the ceramic also showed exceptional discharging performance including a fast discharge rate (τ_0.9 < 70 ns), an ultrahigh discharge current density (1104 A cm⁻²) and a high power density (82.8 MW cm⁻³). The achieved capacitive performance in this work indicates the great potential of the designed novel tungsten bronze ceramic for energy storage applications.

High-temperature dielectric composite films of all-organic PVDF/ABS were fabricated. The composites possessed excellent temperature stability. Ultrahigh U_discharged (11.42 J cm⁻²) and high efficiency (75.8%) at 100 °C were simultaneously achieved.