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The hydrolysis/methanolysis of silicon has received considerable attention to achieve efficient and on-demand hydrogen conversion. However, the intense covalent network and highly localized electrons in pure Si impede its reactivity with water (H 2 O) or methanol (CH 3 OH), thereby hindering the hydrogen release. In this work, we report the synthesis of Zintl phase alkalis-Si alloys via simple ball-milling or sintering, showing eminent performance in enhancement of H 2 O/CH 3 OH dissociation. Experiments combined with DFT calculations have revealed that the obtained Zintl phase alloys exhibit discrete Si clusters containing well-defined unpaired electrons that efficiently facilitate the interaction between reductant and solvent molecules. Such an effect thereby reduces the activation barrier of H 2 O/CH 3 OH dissociation to yield active intermediates containing Si-H structure, which significantly promotes the hydrogen release with favorable kinetics and efficiency. The optimal Zintl Li 21 Si 5 alloy achieves ultrahigh Si utilization rates of 86.9% in water and 98.1% in methanol at 25 °C, respectively. Remarkably, even at an extremely low temperature of −40 °C, a substantial hydrogen yield of 1.091 L g − 1 in methanol is retained. Furthermore, the desirable Zintl phase-water reaction inspires an economic-friendly “charge-hydrolysis-separation” strategy, for effectively recovering the valuable lithium, graphite, Si and Cu resources from the degraded lithium-ion batteries. Si-based hydrogen generation via hydrolysis/methanolysis faces reactivity challenges. Here, zintl-phase alkali–Si alloys, featuring discrete Si clusters with unpaired electrons, efficiently lower activation barriers, enabling high-yield, low-temperature H 2 release.

Highlights There is a novel “hydrolysis-driven synthesis” approach for the preparation of a dual-surface functionalized micron-sized Si anode with a SiO x /C layer. The functionalized inner pores and dual-functional SiO x /C layer synergistically alleviate volume change of Si lithiation, minimize stress concentration and improve electrochemical reaction kinetics. The optimized micron-Si anode performs impressive lifespan, excellent high rate capacity and outstanding stack cell volumetric energy density. Micro-silicon (Si) anode that features high theoretical capacity and fine tap density is ideal for energy-dense lithium-ion batteries. However, the substantial localized mechanical strain caused by the large volume expansion often results in electrode disintegration and capacity loss. Herein, a microporous Si anode with the SiO x /C layer functionalized all-surface and high tap density (~ 0.65 g cm⁻ 3 ) is developed by the hydrolysis-driven strategy that avoids the common use of corrosive etchants and toxic siloxane reagents. The functionalized inner pore with superior structural stability can effectively alleviate the volume change and enhance the electrolyte contact. Simultaneously, the outer particle surface forms a continuous network that prevents electrolyte parasitic decomposition, disperses the interface stress of Si matrix and facilitates electron/ion transport. As a result, the micron-sized Si anode shows only ~ 9.94 GPa average stress at full lithiation state and delivers an impressive capacity of 901.1 mAh g⁻ 1 after 500 cycles at 1 A g⁻ 1 . It also performs excellent rate performance of 1123.0 mAh g⁻ 1 at 5 A g⁻ 1 and 850.4 at 8 A g⁻ 1 , far exceeding most of reported literatures. Furthermore, when paired with a commercial LiNi 0.8 Co 0.1 Mn 0.1 O 2 , the pouch cell demonstrates high capacity and desirable cyclic performance.

Metal atoms often locate in energetically favorite close-packed planes, leading to a relatively high penetration barrier for other atoms. Naturally, the penetration would be much easier through non-close-packed planes, i.e. high-index planes. Hydrogen penetration from surface to the bulk (or reversely) across the packed planes is the key step for hydrogen diffusion, thus influences significantly hydrogen sorption behaviors. In this paper, we report a successful synthesis of Mg films in preferential orientations with both close- and non-close-packed planes, i.e. (0001) and a mix of (0001) and (10 3), by controlling the magnetron sputtering conditions. Experimental investigations confirmed a remarkable decrease in the hydrogen absorption temperature in the Mg (10 3), down to 392 K from 592 K of the Mg film (0001), determined by the pressure-composition-isothermal (PCI) measurement. The ab initio calculations reveal that non-close-packed Mg(10 3) slab is advantageous for hydrogen sorption, attributing to the tilted close-packed-planes in the Mg(10 3) slab.

Micro-electrical discharge machining (micro-EDM) is a good candidate for processing micro-hole arrays, which are critical features of micro-electro-mechanical systems (MEMS), diesel injector nozzles, inkjet printheads and turbine blades, etc. In this study, the wire vibration of the wire electro-discharge grinding (WEDG) system has been analyzed theoretically, and, accordingly, an improved WEDG method was developed to fabricate micron-scale diameter and high-aspect-ratio microelectrodes for the in-process micro-EDM of hole array with hole diameter smaller than 20 μm. The improved method has a new feature of a positioning device to address the wire vibration problem, and thus to enhance microelectrodes fabrication precision. Using this method, 14 μm diameter microelectrodes with less than 0.4 μm deviation and an aspect ratio of 142, which is the largest aspect ratio ever reported in the literature, were successfully fabricated. These microelectrodes were then used to in-process micro-EDM of hole array in stainless steel. The effects of applied voltage, current and pulse frequency on hole dimensional accuracy and microelectrode wear were investigated. The optimal processing parameters were selected using response–surface experiments. To improve machining accuracy, an in-process touch-measurement compensation strategy was applied to reduce the cumulative compensation error of the micro-EDM process. Using such a system, micro-hole array (2 × 80) with average entrance diameter 18.91 μm and average exit diameter 17.65 μm were produced in 50 μm thickness stainless steel sheets, and standard deviations of hole entrance and exit sides of 0.44 and 0.38 μm, respectively, were achieved.

Surface structures with micro-grooves have been reported to be an effective way for improving the performance of metallic components. Through-mask electrochemical micromachining (TMEMM) is a promising process for fabricating micro-grooves. Due to the isotropic nature of metal dissolution, the dissolution of a workpiece occurs both along the width and depth. Overcut is generated inevitably with increasing depth, which makes it difficult to enhance machining localization. In this paper, a method of electrochemical machining using a conductive masked porous cathode and jet electrolyte supply is proposed to generate micro-grooves with high machining localization. In this configuration, the conductive mask is directly attached to the workpiece, thereby replacing the traditional insulated mask. This helps in achieving a reduction in overcut and an improvement in machining localization. Moreover, a metallic nozzle is introduced to supply a jetted electrolyte in the machining region with enhanced mass transfer via a porous cathode. The simulation and experimental results indicate that as compared with an insulated mask, the use of a conductive mask weakens the electric field intensity on both sides of machining region, which is helpful to reduce overcut and enhance machining localization. The effect of electrolyte pressure is investigated for this process configuration, and it has been observed that high electrolyte pressure enhances the mass transfer and improves the machining quality. In addition, as the pulse duty cycle is decreased, the dimensional standard deviation and roughness of the fabricated micro-groove are improved. The results suggest the feasibility and reliability of the proposed method.

Passive smoking is extensively studied because of its harmfulness to human health. In this study, the effects of fermented green tea waste extract gels (GTEG) on oxidative damage in mice exposed to short-term cigarette smoke (CS) were investigated. The GTEG is prepared from green tea waste extract and microbial transglutaminase (MTGase). The lung injury model of mice was established through passive smoking for 5 days. The experimental results revealed the following findings. (1) The GTEG induced by MTGase has obvious gel properties; (2) GTEG has strong biological activity and antioxidant properties in vitro; (3) The passive smoking model was established successfully; specifically, the lung tissue of the model mice exhibited inflammatory symptoms, oxidative stress response appeared in their bodies, and their inflammatory indicators increased; (4) Compared with the passive smoking model group, the mice, which were exposed to CS and received GTEG treatment, exhibited increased food intake and body weight; increased total superoxide dismutase and glutathione peroxidase activity in serum; significant decreases (p < 0.05) in the content levels of the inflammatory factors malondialdehyde, interleukin (IL)-6, and tumor necrosis factor α (TNF-α); and inhibited expression of IL-6, IL-33, TNF-α, and IL-1β inflammatory genes. The results indicated that taking GTEG can relieve the oxidative stress injury of mice caused by short-term CS and has antioxidant properties.

Traditional micromilling leaves burrs and has a high surface roughness in the workpiece, which compromises the microstructural machining quality. Electrophoresis-assisted ultrasonic micromilling machining (EUMM) is proposed to solve this problem. An electrophoresis assisted electric field is applied to attract abrasive particles into the machining gap. Combined with the ultrasonic vibrations of the workpiece, the impact and grinding effect of these abrasive particles in the machining gap removes burrs that are generated during machining and reduces the surface roughness of the microstructure. Micro channels were generated for this study to verify the proposed method. The experimental results show that the EUMM significantly reduces burr formation during microchannel milling. The EUMM also decreases the surface roughness (Ra); the bottom roughness using the EUMM (0.33 µm) is lower than that with either the ultrasonic micromilling (UMM) or traditional micromilling. The EUMM also improves the sidewall roughness since the grinding and particle impacts significantly smooth the sidewalls. The particles during EUMM ensure a low surface roughness of 0.34 µm for the vertical sidewalls. Furthermore, the EUMM has a lesser effect on the width of the micro channels; as the spindle speed increases, the microchannel width only increases from 486 to 498 µm.

Magnesium hydride (MgH2) exhibits great potential for hydrogen and lithium storage. In this work, MgH2-based composites with expanded graphite (EG) and TiO2 were prepared by a plasma-assisted milling process to improve the electrochemical performance of MgH2. The resulting MgH2–TiO2–EG composites showed a remarkable increase in the initial discharge capacity and cycling capacity compared with a pure MgH2 electrode and MgH2–EG composite electrodes with different preparation processes. A stable discharge capacity of 305.5 mAh·g−1 could be achieved after 100 cycles for the 20 h-milled MgH2–TiO2–EG-20 h composite electrode and the reversibility of the conversion reaction of MgH2 could be greatly enhanced. This improvement in cyclic performance is attributed mainly to the composite microstructure by the specific plasma-assisted milling process, and the additives TiO2 and graphite that could effectively ease the volume change during the de-/lithiation process as well as inhibit the particle agglomeration.

Rare-earth-based AB2-type compounds with Laves phase structure are readily subject to hydrogen-induced amorphization and disproportionation upon hydrogenation. In this work, we conducted the Sc alloying on Y0.95Ni2 to improve its hydrogen storage properties. The results show that the amorphization degree of Y0.95Ni2 deepens with the increasing hydrogenation time, pressure, and temperature. The Y(Sc)0.95Ni2 ternary compounds show a significant improvement in reversibility and dehydriding thermodynamics due to the reduced atomic radius ratio RA/RB and cell volume. Hydrogen-induced amorphization is fully eliminated in the Y0.25Sc0.7Ni2. The Y0.25Sc0.7Ni2 delivers a reversible hydrogen storage capacity of 0.94 wt.% and the dissociation pressure of 0.095 MPa at the minimum dehydrogenation temperature of 100 °C.

The enhancement of display performance and durability in polymer-stabilized vertical alignment liquid crystal and the liquid crystal are negative liquid crystals, which can be vertically aligned under the action of a vertical orientation layer and an electric field. Devices (PSVA LCDs) are crucial for advancing LCD technology. This study aims to investigate the electro-optical characteristics of PSVA LCDs by varying polymerization monomer concentrations. Using both simulations via TechWiz LCD 3D and experimental methods, such as polymer-induced phase separation, we developed an optoelectronic testing framework to assess voltage transmittance and response times. In our main findings, we show that an increase in polymeric monomer concentration from 3% to 7% resulted in a 67% increase in threshold voltage and a 44% decrease in saturation voltage. The on-state response time increased by about a factor of three, while the off-state response time decreased by about a factor of three. The alignment of our simulation results with experimental data validates our methodology, offering the potential of simulation tools as a pivotal resource in the PSVA LCDs. The alignment of our simulation results with experimental data validates our methodology, offering the potential of simulation tools as a pivotal resource in the PSVA LCDs. These advancements promise significant improvements in PSVA LCD performance and durability.