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Dielectric materials featured with polarization at an applied electric field have been demonstrated with a wide range of applications such as energy storage and conversion, thus triggering tremendous efforts in scientific and industrial research. To date, numerous strategies have been explored to improve the performance of dielectric materials; especially, the recently reported high-entropy design enabling flexible composition configuration and tunable functional properties has attracted increasing attention. In this contribution, we review the very recent investigations and applications of high-entropy design for dielectric materials, including dielectric energy storage, electrocalorics, piezoelectrics, and ferroelectrics, and address the challenges and remaining concerns. Finally, we suggest future research directions for the preparation and in-depth structure characterization of high-entropy dielectric materials. This review will provide a holistic view of the most state-of-the-art high-entropy dielectric materials and envision prospects of high-entropy design for dielectrics. [ABSTRACT FROM AUTHOR]

To meet the miniaturization demands of next-generation electronics and electrical systems, energy storage capacitors with both high energy density and efficiency have become a research hotspot. Ferroelectric-based dielectrics are primary candidates due to the existence of spontaneous polarization and versatile domain structures. Since domains are fundamental structure units that respond to the external electric field, domain engineering is a general route to realizing high energy storage performance. In this perspective, we introduce a type of dielectrics, proposed recently and termed superparaelectrics, which has ultrasmall polar clusters (several unit cells) and exhibits nearly zero hysteresis and relatively high polarization due to the highly dynamical polar structure. Fundamental concepts of superparaelectricity are overviewed, and representative examples with state-of-the-art energy storage performance are reviewed to demonstrate the advantages of superparaelectrics. Finally, perspectives are provided about the future development of superparaelectric and electrostatic energy storage fields. [ABSTRACT FROM AUTHOR]

Advanced ceramic aerogel materials with a performance combining sufficient mechanical robustness and splendid high-temperature resistance are urgently needed as thermal insulators in harsh environments. However, the practical applications of ceramic aerogel materials are always limited by poor mechanical performance and degradation under thermal shock. Here, we report the facile creation of lamellar multiarch structured ceramic nanofibrous aerogels that are simultaneously ultrastrong, superelastic, and high temperature resistant by combining ZrO 2 -Al 2 O 3 nanofibers with Al(H 2 PO 4 ) 3 matrices. The resulting ZrO 2 -Al 2 O 3 nanofibrous aerogels exhibit the integrated properties of rapid recovery from a strain of 90%, high compression strength of more than 1100 kPa (at a strain of 90%), high fatigue resistance, and temperature-invariant superelasticity. Moreover, the all-ceramic component feature also provides the ceramic nanofibrous aerogels with high-temperature resistance up to 1300 °C and thermal insulation performance with low thermal conductivity (0.0322 W m -1 K -1 ). These superior performances make the ceramic aerogels ideal for high-temperature thermal insulation materials in extreme conditions.

Constructing nanostructured catalyst-embedded ceramic fibrous membranes would facilitate the remediation or preliminary treatment of dyeing wastewater, however, most of such membranes are brittle with low deformation resistance, thus, restricting their widely applications. Herein, the flexible and hierarchical nanostructured MnO 2 -immobilized SiO 2 nanofibrous membranes (MnO 2 @SiO 2 NFM) were fabricated by combining the electrospinning technique with hydrothermal method. The morphologies of membranes could be regulated from nanowires and nanoflower to mace-like structure via varying concentration of reactants. The resultant MnO 2 @SiO 2 NFM could cooperate with hydrogen peroxide to form a Fenton-like reagent for the degradation of methylene blue (MB). The resultant membrane exhibited prominent catalytic performance towards MB, including high degradation degree of 95% within 40min, fast degradation rate of 0.0865min -1 , and excellent reusability in 5 cycles. Moreover, the membranes could be used in a wide pH range of 0 to 14 and the degradation degree reached 76% during dynamic filtration process with a flux of 490,000Lm -2 h -1 . The successful fabricating of such membrane with extraordinary catalytic performance would provide a platform for preparing high-performance catalysts for remediation of dyeing wastewater., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Functional nanoparticles modified silica nanofibrous materials with good flexibility, a hierarchical mesoporous structure, and excellent durability would have broad applications in efficient removal of contaminants, yet have proven to be enormously challenging to construct. Herein, we reported a strategy for rational design and fabricating flexible, hierarchical mesoporous, and robust ZrO 2 nanoparticle-embedded silica nanofibrous membranes (ZrO 2 /SiO 2 NM) for phosphate removal by combining the chitosan dip-coating method with the electrospinning technique. Our approach allows ZrO 2 nanoparticles to be in situ firmly and uniformly anchored onto SiO 2 nanofibers to drastically enlarge the specific surface area and porosity of membranes. Therefore, the resultant ZrO 2 /SiO 2 NM exhibited a prominent removal efficiency of 85% and excellent adsorption amount of 43.8 mg P g -1 membranes in 30 min toward phosphates. Furthermore, the removal performance toward different types of phosphates revealed that the resultant membranes also could be used to remove phosphates in detergent and fertilizer water samples. More importantly, the membranes with good flexibility could directly be taken out from solution after use without any post-treatment. Such a simple and intriguing approach for fabricating nanofibrous membranes may provide a new platform for constructing membranes with superb phosphate removal performance.