Nonbattery behavior related phase transition of electrodes is usually not favorable for any batteries because it results in performance degradation at all times. Here, we demonstrate a zinc hybrid-ion battery (ZHIB) with an unusual capacity enhancement even within 18 000 cycles by employing V2CTX MXene as the cathode, enormously differing from all reported counterparts with capacity degradation initiated within hundreds of cycles. The dominated mechanisms are determined to be MXene delamination and an unexpected phase transition during cycling. Both the original cathode and secondary derivative contribute to capacity simultaneously, resulting in the unusual capacity enhancement. Consequently, the specific capacity of 508 mAh g–1 (highest for all reported aqueous zinc-ion batteries) and high energy density of 386.2 Wh kg–1 are realized. Also, the quasi-solid-state batteries fabricated can output stably at −20 °C and in bending, twisting, stabbing, and cutting conditions. Our work brings an effective approach, that is, utilizing “unstable” electrode materials, which should usually be avoided, to achieve continuously enhanced performance of a battery. The idea to use both original and secondary materials for energy storage may be developed to be a general method to achieve extraordinary cycling stability of batteries.

Nanofibers or nanofibrous membranes prepared by electrospinning possess many attractive properties, including excellent mechanical properties, high specific surface area and high porosity, making them attractive for sensor application, especially for the electrochemical sensors. Many nanomaterials are used as additives to improve the conductivity, sensitivity and selectivity of sensors. Based on the different modifiers of electrode materials, electrochemical sensors can be divided into enzyme sensors and non-enzyme sensors. In this review, we summarize the recent progress of the electrochemical sensors fabricated by electrospinning, including hydrogen peroxide (H2O2) sensors, glucose sensors and other sensors. In addition, the sensing mechanisms of various electrochemical sensors are introduced in detail. Finally, future research directions of electrochemical sensors based on electrospinning and the challenges faced by large-scale applications of electrospun electrochemical sensors are presented.

Abstract. In this paper we prove the equidistribution of certain families of special subvarieties in Kuga varieties, which is a special case of the general André-Oort conjecture formulated for mixed Shimura varieties. Our approach is parallel to the pure case treated in the works of L. Clozel, E. Ullmo, and A. Yafaev, which uses tools from ergodic theory.

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Facilitating phase conversion efficiency of Li polysulfides to Li2S and restraining the dissolution of Li polysulfides are critical for stable lithium–sulfur (Li–S) batteries. Herein, an in situ formed sulfiphilic superfine Fe2O3 nanocrystals confined in lithiophilic N‐doped microporous carbon (Fe2O3/N‐MC) is derived from one‐step hypercrosslinked polymerization. Uniquely, the dual active sites (Fe2O3 and N) in Fe2O3/N‐MC tend to form “FeS, LiO or LiN” bonding, and then synchronically enhancing the chemisorption and interface conversion ability of Li polysulfides. As a result, 80 wt% S is loaded on Fe2O3/N‐MC and the hybrid cathode delivers high mass capacity (730 mA h g‐1) and excellent cycling stability (87.1% capacity retention over 1000 cycles at 5.0 C). Especially, the cathode also exhibits a high reversible areal capacity of 3.69 mA h cm‐2 at a high areal loading (5.1 mg cm‐2) and a lean electrolyte/sulfur (E/S) ratio (7.5 µL mg‐1) over 500 cycles. This work is anticipated to deepen the comprehension of complex Li polysulfides interphase conversion processes and afford new thoughts for designing new host materials.

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In this paper, glass fiber-reinforced polyamide-6 (PA-6) composites with up to 70 wt% fiber contents were successfully manufactured using a pultrusion process, utilizing the anionic polymerization of caprolactam (a monomer of PA-6). A novel thermoplastic reaction injection pultrusion test line was developed with a specifically designed injection chamber to achieve complete impregnation of fiber bundles and high speed pultrusion. Process parameters like temperature of injection chamber, temperature of pultrusion die, and pultrusion speed were studied and optimized. The effects of die temperature on the crystallinity, melting point, and mechanical properties of the pultruded composites were also evaluated. The pultruded composites exhibited the highest flexural strength and flexural modulus, reaching 1061 MPa and 38,384 MPa, respectively. Then, effects of fiber contents on the density, heat distortion temperature, and mechanical properties of the composites were analyzed. The scanning electron microscope analysis showed the great interfacial adhesion between fibers and matrix at 180 °C, which greatly improved the mechanical properties of the composites. The thermoplastic reaction injection pultrusion in this paper provided an alternative for the preparation of thermoplastic composites with high fiber content.

Continuous glass fiber reinforced polylactic acid (CGF/PLA) composites were prepared by 3D printing technology in this study. The multi-roll melt impregnation mold was manufactured according to the melt impregnation model. CGF/PLA filament was prepared by a melt impregnation device, and then used to prepare CGF/PLA composite materials by the self-modified 3D printer device. The full impregnation of the fibers was achieved by the action of the coverage angle of the tension roller in the impregnation mold. The effects of the total coverage angle, traction speed, fiber content, and impregnation temperature on the fiber impregnation effect and 3D printed product performance were studied. The bending strength, tensile strength, impact strength, and interlayer shear strength of the printed sample reached 312, 220, 154, and 14 MPa, respectively. The strategy in this study can effectively improve the impregnation effect of PLA resin on CGFs and promote the development and application of 3D printing technology in the field of high-performance composite manufacturing.