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Recent advances of photonic crystals are driven to mechanical sensors and smart wearable devices; however, for chiral photonic cellulose nanocrystal (CNC) materials, vivid structural coloration and reversible mechanochromism like chameleon skin remain a big challenge. Here, we report a ternary co-assembly and post-UV-irradiation polymerization strategy to develop flexible and elastic CNC composite films, which, notably, have naked-eye-visible brilliant structural colors and stretching-induced color change covering a broad wavelength region at a moderate deformation (like skin). By adjusting the stretching, the film is designed as a smart skin to adapt to surrounding environments for camouflage. This work offers a universal strategy for constructing biomimic optically functional cellulose skins.

Well-crystallized perovskite ferroelectric films usually display a bulk-like polarization response (P) under an external electric field (E), i.e., a large P-E hysteresis loop featuring a sizable remnant polarization and an early polarization saturation. Such characteristics are undesirable for capacitive energy storage applications. In this work, we demonstrate an optimal P-E behavior, i.e., a small remnant polarization and a delayed polarization saturation, in perovskite BaTiO3 films consisting of superfine columnar nanograins. In a low-temperature, nucleation-dominated sputtering deposition, an in-situ grown conductive buffer layer promotes the formation of these nanograins, which display a controllable diameter down to ~10 nm and extend throughout the film thickness. The deterioration of the remnant polarization and its delayed saturation under an electric field, can be attributed to a strong polarization-constraining effect from the densely-packed, non-ferroelectric grain boundaries, which is supported by a phase field modeling simulation. The resulted BaTiO3 film capacitors integrated on Si at 350°C display a high recyclable energy density (Wrec~135±10 J/cm3) and efficiency (η~80%±4%) which are thickness-scalable. An intrinsically high power density, a simple and stable chemical composition, and good thermal (-150°C ~ 170°C) and cycling stabilities (up to ~ 2 × 108 charge-discharge cycles) warrant a broad range of applications for these film capacitors.

BaTiO3-based ferroelectrics have been extensively studied due to their large dielectric constants and a high saturated polarization, which have the potential to store or supply electricity of very high energy and power densities. In order to further improve the energy efficiency η and the recyclable energy density Wrec, an A, B-site co-doped (Ba0.95,Sr0.05)(Zr0.2,Ti0.8)O3 ceramic target was used for sputter deposition of film capacitor structures on Si. This film composition reduces the remnant polarization Pr, while the choice of a low-temperature, templated sputtering process facilitates the formation of high-density arrays of columnar nanograins (average diameter d ∼20 nm) and grain boundary dead layers. This self-assembled nanostructure further delays the saturation of the electric polarization, leading to a high energy density Wrec of ∼148 J/cm3 and a high energy efficiency η of ∼90%. Moreover, the (Ba0.95,Sr0.05)(Zr0.2,Ti0.8)O3 film capacitors retain their high energy storage performance in a broad range of working temperature (-175-300 °C) and operating frequency (1 Hz-20 kHz). They are also fatigue-free after up to 2 × 109 switching cycles. Our work provides a new method and a cost-effective processing route for the creation and integration of high-performance dielectric capacitors for energy storage applications.

Using a modified Landau-Devonshire type thermodynamic potential, we show that dielectric tunability η of a tetragonal ferroelectric film can be analytically solved. At a given electric field E, η is a function of the remnant polarization ($$P_0^f$$ P 0 f ) and the small-field relative dielectric permittivity ($$\chi _0^f$$ χ 0 f ), which are commonly measured material properties. After a survey of materials, a large η~80% is predicted to be achievable in a (001)-oriented tetragonal (K0.5,Na0.5)NbO3 film. This strain-stabilized tetragonal phase is verified by density functional theory (DFT) calculations. (K0.5,Na0.5)NbO3 films based on this design were successfully prepared via a sputtering deposition process on SrRuO3-buffered (100)SrTiO3 substrates. The resulted epitaxial films showed a sizable $$P_0^f$$ P 0 f (~0.21C m−2) and a large $$\chi _0^f$$ χ 0 f (~830–860), as well as a large η close to the theoretical value. The measured dielectric tunabilities as functions of E are well described by the theoretical η(E) curves, validating our integrated approach rooted in a theoretical understanding.

High energy density dielectric film capacitors are desirable in modern electronic devices. Their miniaturization and integration into Si-based microsystems create opportunities for in-circuit energy supply, buffering, and conditioning. Here, we present a CMOS (complementary metal oxide semiconductor)-compatible route for the fabrication of BaTiO

BaTiO

Cellulose nanocrystal (CNC) is an interesting polysaccharide nanomaterial that can self-assemble into a chiral nematic liquid crystalline structure in aqueous solution, producing brightly structural color upon selectively reflection of visible light. However, till now, only iridescent structural colors can be created by such colloidal array, making it impossible to be used as colorimetric sensors. Here, inspired by longhorn beetle having short-range ordered but long-range disordered microstructures, it is demonstrated to develop low-/non-angle-dependent structural-color CNC composite films through interference against the long-range orders as a result of introducing positively charged poly (dimethyl diallyl ammonium chloride) (PDDA). By exploring balanced ordered/disordered structures, vivid angle-independent structural colors are realized, enabling accurate cognition for environmental signals, which is crucial to promising applications in sensing, anti-counterfeit, and decoration technology.

Dielectric capacitors have the highest charge/discharge speed among all electrical energy devices, but lag behind in energy density. Here we report dielectric ultracapacitors based on ferroelectric films of Ba(Zr0.2,Ti0.8)O3 which display high-energy densities (up to 166 J cm–3) and efficiencies (up to 96%). Different from a typical ferroelectric whose electric polarization is easily saturated, these Ba(Zr0.2,Ti0.8)O3 films display a much delayed saturation of the electric polarization, which increases continuously from nearly zero at remnant in a multipolar state, to a large value under the maximum electric field, leading to drastically improved recyclable energy densities. This is achieved by the creation of an adaptive nano-domain structure in these perovskite films via phase engineering and strain tuning. The lead-free Ba(Zr0.2,Ti0.8)O3 films also show excellent dielectric and energy storage performance over a broad frequency and temperature range. These findings may enable broader applications of dielectric capacitors in energy storage, conditioning, and conversion., Dielectric capacitors offer high-power delivery materials for energy-storage, yet suffer from low energy densities. Here, the authors prepared ferroelectric Ba(Zr0.2,Ti0.8)O3 that utilizes polydomain nanostructures to delay electric polarization saturation and boost energy densities.

Natural-superlattice-structured/intergrowth CaBi 2 Nb 2 O 9 -Bi 4 Ti 3 O 12 (CBNO-BIT) ferroelectric thin films were successfully prepared via a magnetron sputtering process. XRD and TEM analysis revealed the [Bi 2 O 2 -(CaNb 2 O 7 )-Bi 2 O 2 -(Bi 2 Ti 3 O 10 )] n intergrowth structure of the film, as well as a (200)/(020) texture. XPS and EDS results confirmed that the film composition is close to the chemical stoichiometry. With its microstructure being successfully tailored at the nanoscale, the CBNO-BIT film exhibits good electrical properties, including a large dielectric constant ( e r ∼390), a high piezoelectric coefficient ( d 33 ∼90 pm/V) as well as a high energy storage density ( W E ∼76 J/cm 3 ). Finally, the intergrowth nature of the film was verified by the measured temperature-dependent dielectric response (C-T).

Genus Rambutanura Deharveng, 1988 of subfamily Neanurinae is herein recorded and a new species is described from China. A key to the species of the whole world of the genus is provided. In order to determine the new species, a new diagnosis within the genus Rambutanura Deharveng, 1988 is proposed. The new species is distinguished from all known members of the genus by its unique set of morphological characters notably: 2+2 depigmented eyes, mandible quadridentate, presence of 1 additional s-chaeta on each tubercle Di from Th. I to Abd. IV, presence of 2 additional s-chaetae on tubercle Dl from Abd. I to Abd. V, presence of guard chaetae sgd and sgv on AOIII, absence of digitate body tubercles.

To observe the anti-liver-fibrosis effect of Guzhang Tablet (GZT) and to explore its mechanism.Fifty female rats, weighing 200-220 g were randomly divided into the blank control group, the model group, the small dosage GZT group, the large dosage GZT group and the Biejiajian Pill (BJJP) group, 10 rats in each group. The changes of related serum enzymes, liver-fibrosis marker, oxygen free radical and liver tissue pathology were observed after 8 weeks of treatment.(1) Compared with the model group, the serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST), glutamyltranspetidase (GGT), alkaline phosphatase (AKP) were improved in the GZT groups, better effect was got in the large dosage GZT group. (2) Compared with the blank control group, GZT showed no effect on serum total protein (TP) but with raising albumin (ALB) effect. (3) Compared with blank control group, the levels of hyaluronidase (HA), laminin (LN), collagen type IV (IV-C) and procollagen type III (PC III) in both GZT groups were lower, especially in the large dosage GZT group. (4) Small and large dosage of GZT showed effect in reducing malonyldialdehyde (MDA), Glutathione-peroxidose(GSH-Px) and nitric oxide (NO) content, but the effect on increasing superoxide dismutase (SOD) similar to that of BJJP with no significant different. (5) GZT, both small and large dosage, had obvious anti-liver fibrosis action, which was superior to that of BJJP.In the genetic and developing processes of liver fibrosis in rats, GZT could protect the liver cells, inhibit the synthesis and reduce the content of collagens, the mechanism might be related with its action in antagonizing peroxidation injury, indicating that GZT could effectively prevent liver fibrosis formation.