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V2CTx MXene is a "rising star" cathode material for aqueous zinc‐based batteries (AZBs) owing to its large/flexible interlayer spacing, rich redox chemistry of V, and high electronic conductivity. Nevertheless, the plentiful F surface terminations generated during the common preparation (fluorine‐containing acid etching process) of V2CTx generally result in high hydrophobicity, poor Zn affinity, and sluggish ion‐diffusion kinetics. Herein, a novel OH‐termination‐rich V2CTx material with interlayer "K+‐pillars" (alk‐V2CTx) is fabricated via a facile one‐step alkalization method, which features excellent hydrophilicity, expanded ion‐transport channels, and robust layered structure. Impressively, the tailored alk‐V2CTx cathode enables highly reversible and rapid Li+/Zn2+ co‐insertion/extraction electrochemistry in the formulated 15 m LiTSFI + 1 m Zn(CF3SO3)2 aqueous electrolyte, meanwhile, the "self‐exfoliation" phenomenon of MXenes upon cycling significantly increases the active sites, rendering the superior rate performance (498.2/195.1 mAh g−1 at 0.1/30 A g−1, respectively) and exceptional cycling life (96.2% capacity retention over 20 000 cycles). Systematic in situ/ex situ analyses and theoretical computations elucidate the above hybrid‐ion storage mechanisms. Finally, flexible quasi‐solid‐state rechargeable Zn batteries employing the alk‐V2CTx cathode exhibit inspiring energy output even under severe deformation conditions and low temperatures. This study provides new perspectives for designing high‐performance MXene‐based cathodes for AZBs by modulating surface terminations. [ABSTRACT FROM AUTHOR]

The development of high‐energy and long‐lifespan NASICON‐type cathode materials for sodium‐ion batteries has always been a research hotspot but a daunting challenge. Although Na4MnCr(PO4)3 has emerged as one of the most promising high‐energy‐density cathode materials owing to its three‐electron reactions, it still suffers from serious structural distortion upon repetitive charge/discharge processes caused by the Jahn‐Teller active Mn3+. Herein, the selective substitution of Cr by Zr in Na4MnCr(PO4)3 was explored to enhance the structural stability, due to the pinning effect of Zr ions and the ≈2.9‐electron reactions, as‐prepared Na3.9MnCr0.9Zr0.1(PO4)3/C delivers a high capacity retention of 85.94% over 500 cycles at 5 C and an ultrahigh capacity of 156.4 mAh g−1 at 0.1 C, enabling the stable energy output as high as 555.2 Wh kg−1. Moreover, during the whole charge/discharge process, a small volume change of only 6.7% was verified by in situ X‐ray diffraction, and the reversible reactions of Cr3+/Cr4+, Mn3+/Mn4+, and Mn2+/Mn3+ redox couples were identified via ex situ X‐ray photoelectron spectroscopy analyses. Galvanostatic intermittent titration technique tests and density functional theory calculations further demonstrated the fast reaction kinetics of the Na3.9MnCr0.9Zr0.1(PO4)3/C electrode. This work offers new opportunities for designing high‐energy and high‐stability NASICON cathodes by ion doping. [ABSTRACT FROM AUTHOR]

Due to the low density of the green part produced by selective laser sintering (SLS), previous reports mainly improve the sample's density through the infiltration of low-melting metals or using isostatic pressing technology. In this study, the feasibility of preparing high-density 316L stainless steel using 316L and epoxy resin E-12 as raw materials for SLS combined with debinding and sintering was investigated. The results indicated that in an argon atmosphere, high carbon and oxygen contents, along with the uneven distribution of oxygen, led to the formation of impurity phases such as metal oxides, including Cr2O3 and FeO, preventing the effective densification of the sintered samples. Hydrogen-sintered samples can achieve a high relative density exceeding 98% without losing their original design shape. This can be attributed to hydrogen's strong reducibility (effectively reducing the carbon and oxygen contents in the samples, improving their distribution uniformity, and eliminating impurity phases) and hydrogen's higher thermal conductivity (about 10 times that of argon, reducing temperature gradients in the sintered samples and promoting better sintering). The microstructure of the hydrogen-sintered samples consisted of equiaxed austenite and ferrite phases. The samples exhibited the highest values of tensile strength, yield strength, and elongation at 1440 °C, reaching 513.5 MPa, 187.4 MPa, and 76.1%, respectively. [ABSTRACT FROM AUTHOR]

The sphericity and fluidity of the powder play a crucial role in the forming and sintering of ceramics. High‐performance AlON spherical powder was prepared for the first time by spray drying of powder fired by solid‐phase reaction, and the preparation of AlON transparent ceramics was realized under pressureless sintering conditions. The effect of AlN dosage on the purity of AlON powder was investigated, and the powder fluidity was improved by spray drying technique. Then the best spray drying process was selected by scanning electron microscopy, AD/TD, green density, MIP and transmittance measurements. The AlON particles obtained under the optimal granulation process have good dispersibility, high green density after pressing, and uniform pore distribution. After dry pressing and sintering at 1900°C for 20 h, the AlON ceramics with linear transmissivity of 84.3% at 2 μm wavelength can be obtained. The excellent pressing and sintering properties of AlON granulated particles make it possible for large‐scale production. [ABSTRACT FROM AUTHOR]

The sulfide-based solid electrolyte (SSE) has been considered as a strong candidate for potential uses in all-solid-state lithium batteries (ASSLBs). Nevertheless, most of the reported SSEs are plagued with their intrinsic air-sensitive behaviors and Li-incompatibility, which largely preclude scalable fabrication and widespread practical application. Herein, we report the Li6+xSb1−xSnxS5I (LSSSI-x) SSEs using nontoxic inexpensive Sn substitution to deal with these issues. The ionic conductivity of Li6+xSb1−xSnxS5I can achieve a maximum value of 3.49 × 10−4 S cm−1 at room temperature when x = 0.4, which is over 40-fold that of the pristine Li6SbS5I. The Li symmetric cell with I-rich Li6.4Sb0.6Sn0.4S5I (LSSSI-0.4) electrolyte delivers a stable Li+ plating/stripping behavior over 450 h at a current density of 0.1 mA cm−2. Benefiting from the decent Li-compatibility of LSSSI-0.4, the assembled ASSLB with LiNi0.8Co0.1Mn0.1O2-based composite cathode and Li-metal anode displays good cycling performance. The LSSSI-0.4 electrolyte also possesses excellent moisture stability. ASSLB using the dried LSSSI-0.4 electrolyte still exhibits a well-maintained initial discharge capacity of 184.0 mA h g−1 at 0.1C and an impressive capacity retention rate of 70.6% after 600 cycles at 0.2C. This work offers a feasible option with superior integrated properties to push forward the advancement of high-performance ASSLBs. [ABSTRACT FROM AUTHOR]

The research on how to reduce energy consumption and improve the efficiency of amorphous motors has extensive coverage. This study systematically investigates the influence of internal stress induced by impregnation curing and interference fit on the soft magnetic properties and loss characteristics of Fe80Co3Si3B10P1C3 (CAF4) amorphous alloy iron cores. The amorphous iron core samples undergo analysis through differential scanning calorimetry (DSC), transmission electron microscopy (TEM), X-ray diffraction (XRD), magnetic performance testing equipment, flexible pressure sensors, and magnetostriction testers. The CAF4 amorphous iron core after impregnation curing (AIC) exhibits the lowest loss of P1.2T,1.5 kHz = 22.8 W/kg when annealed at 260 °C, representing a 21% increase compared to the pre-impregnation curing (BIC) state. Within the commonly utilized interference fit range, the loss growth rate of CAF4 amorphous iron cores is lower than that of Fe80Si9B11 (1K101). Likewise, at a frequency of 50 Hz and an excitation of 1000 A/m, the magnetostriction coefficient of CAF4 is smaller than that of 1K101. Within the typical interference fit range, the magnetization performance of CAF4 amorphous iron cores surpasses that of 1K101, favoring lightweight and compact motor designs and reducing copper losses. Consequently, CAF4 amorphous iron cores exhibit significant advantages when employed in motors. [ABSTRACT FROM AUTHOR]