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Lead‐free ferroelectric ceramics are very suitable for electrostatic energy storage capacitors due to their outstanding characteristics of high charge‐discharge speed, high power density, and environmental friendliness. Herein, a novel material system as (1−x)Na0.5Bi0.5TiO3‐xCaZr0.5Ti0.5O3 (NBT‐CZT, x = 0, 0.05, 0.10, 0.12, 0.15, and 0.20) was designed and prepared for dielectric energy storage ceramics. It demonstrated that the CZT additives induced a phase transition for the NBT ceramics, from ferroelectric to relaxor ferroelectric. In particular, extremely high stored energy storage density (6.92 and 5.37 J/cm3), high recoverable energy storage density (4.77 and 4.37 J/cm3), and moderate efficiency (69.0% and 81.4%) were achieved in both the samples of x = 0.12 and x = 0.15, respectively. The ceramics exhibited excellent stability of energy storage performance covering a wide temperature (25°C–200°C) and frequency (0.5–50 Hz) range, and also fatigue cycles up to 105. Additionally, the NBT‐CZT ceramics had a fast discharge speed (t0.9 < 100 ns) and high power density (24.2 MW/cm3, E = 100 kV/cm, x = 0.15), and the charge‐discharge process remained stable even when the measured temperature was up to 160°C. Therefore, the NBT‐CZT ceramics have the potential to be utilized in electrostatic energy storage applications. [ABSTRACT FROM AUTHOR]

With the fast charge‐discharge speed and ultrahigh power density, electrostatic energy storage materials offer great potential in the applications for pulsed power systems. As a very important member of structural ceramics, 3Y‐TZP (3 mol% Y2O3 doped tetragonal zirconia polycrystals) has shown extraordinary mechanical properties. However, the research on their energy storage performance is still lacking. Herein, a ferroelectric phase, BaTiO3 (BT), was introduced and demonstrated to improve the dielectric properties and energy storage performance of 3Y‐TZP ceramic matrix via the conventional solid‐state reaction method. With increasing the BT content from 0 to 15 mol%, the permittivity of the composite ceramics could be effectively increased from 40.2 to 64.1 measured at 1 kHz. Simultaneously, the dielectric loss could be effectively decreased by depressing the response of charged defects, which was further interpreted by the thermally stimulated depolarization current technique. Meanwhile, the breakdown strength showed a typical increase‐then‐decrease trend with increasing BT content, and reached their maximum values when doped with 7 mol% BT. Together with the enhancement of dielectric properties, the 7 mol% BT‐doped 3Y‐TZP ceramics exhibited a maximum energy storage density of 0.42 J/cm3, which was approximately 150% larger than that of the pure 3Y‐TZP ceramics. [ABSTRACT FROM AUTHOR]

Perylenequinonoid natural products are a class of photosensitizers (PSs) that exhibit high reactive oxygen species (ROS) generation and excellent activity for Type I/Type II dual photodynamic therapy. However, their limited activity against gram-negative bacteria and poor water solubility significantly restrict their potential in broad-spectrum photodynamic antimicrobial therapy (PDAT). Herein, a general approach to overcome the limitations of perylenequinonoid photosensitizers (PQPSs) in PDAT by utilizing a macrocyclic supramolecular carrier is presented. Specifically, AnBox·4Cl, a water-soluble cationic cyclophane, is identified as a universal macrocyclic host for PQPSs such as elsinochrome C, hypocrellin A, hypocrellin B, and hypericin, forming 1:1 host-guest complexes with high binding constants (≈10 7 m -1 ) in aqueous solutions. Each AnBox·4Cl molecule carries four positive charges that promote strong binding with the membrane of gram-negative bacteria. As a result, the AnBox·4Cl-PQPS complexes can effectively anchor on the surfaces of gram-negative bacteria, while the PQPSs alone cannot. In vitro and in vivo experiments demonstrate that these supramolecular PSs have excellent water solubility and high ROS generation, with broad-spectrum PDAT effect against both gram-negative and gram-positive bacteria. This work paves a new path to enhance PDAT by showcasing an efficient approach to improve PQPSs' water solubility and killing efficacy for gram-negative bacteria., (© 2024 Wiley‐VCH GmbH.)