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[Display omitted] • Si/SiOx@ZnO@C anode with excellent cycling stability is synthesized from waste silicon. • The fabrication process of Si/SiOx@ZnO@C is discussed in detail. • The addition of zinc oxide and carbon improves the structure stability and transport of Li+ of the electrode. • Excellent electrochemical performance of Si/SiOx@ZnO@C anode is investigated. Silicon anode is deemed to be one of the most promising anode materials and has attracted wide attention from all walks of life. However, its commercial application is severely limited owing to the high cost, serious volume expansion, and poor electrical conductivity. Herein, Si/SiOx nanoparticles were successfully prepared by sand milling the low-cost volatile deposited silicon waste from electron beam refining polycrystalline silicon. Furthermore, the atomic layer deposited (ALD) zine oxide on Si/SiOx nanoparticles enhances the integrity of the electrode structure and provides a steady solid electrolyte layer (SEI). The outer layer is wrapped by a uniform carbon shell to restrict the volume expansion and boost the conductivity of the electrode during lithiation/delithiation. Impressively, lithium-ion batteries (LIBs) employing the Si/SiOx@ZnO@C anodes display excellent rate performance (up to 844.48 mAh g−1 at 2 A g−1) and cycle stability (912.7 mAh g−1 at 1A g−1 over 50 cycles). Moreover, the Si/SiOx@ZnO@C electrode exhibits high initial coulombic efficiency (76.8 %) and the reversible specific capacity maintains at 846 mAh g−1 over 200 cycles with a current density at 0.5 A g−1. The improvement is ascribed to the synergistic effect of triple-protected layer that effectively enhances the stability of SEI and the conductivity of the electrode. This work not only opens a novel and economic strategy for the manufacture of high-performance silicon-based anode but also furnishes an original approach for recycling and resource utilization of silicon waste. [ABSTRACT FROM AUTHOR]

The use of a small amount of MgO dopant can help to improve the performance of Na-β″-Al 2 O 3 electrolyte by enhancing the relative density, promoting the formation of homogeneous and compact microstructure, and increasing the content of β″-Al 2 O 3 phase. In this work, the effects of the amount of MgO dopant and the sintering temperature on the relative density, β″ phase content, and performance of the Na-β″-Al 2 O 3 electrolyte were studied in detail, respectively. The samples were characterized in respects of relative density, closed-cell porosity, XRD, SEM, bending strength, and AC Impedance. The results demonstrated that the addition of MgO dopant significantly improved the densification rate of Na-β″-Al 2 O 3 ceramics. The crucial temperature phase for pore elimination was 1500–1550 °C. Samples doped with 0.2–2.0 wt% MgO formed homogeneous microstructures associated with grain size refinement of the final compact at 1550 °C. Macro defects appeared when sintering temperature reached to 1580 °C. The total conductivity showed a linear dependence on the temperature (200–700 °C), which fitted well with the Arrhenius equation. Na-β″-Al 2 O 3 ceramics doped with 0.4 wt% MgO showed the best bending strength (283 MPa) and preferable ionic conductivity. [ABSTRACT FROM AUTHOR]

Doping a small amount of TiO 2 can promote the relative density, increase the content of β″-Al 2 O 3 phase and improve the microstructure of β″-Al 2 O 3 electrolyte. In this work, the influence of microstructure, relative density, content of β″ phase and performance of β″-Al 2 O 3 electrolyte were studied by adjusting the doping amount of TiO 2 and the sintering temperature. Samples were characterized with respect of density, closed-cell porosity, XRD, SEM, bending strength, AC Impedance Spectroscopy. The results demonstrated that the addition of TiO 2 can significantly improve the densification rate of β″-Al 2 O 3 ceramics. 1500–1550 °C is the key temperature section of eliminating pore process. At 1550 °C, the sample of 0.1–0.8 wt.% TiO 2 formed homogeneous microstructure associated with a refinement in the grain size of the final compact. Macro defects appeared when the sintering temperature reached to 1580 °C or the content of TiO 2 was 1.6–2.0 wt.%. The total conductivity linearly depended on the temperature and fitted well with the Arrhenius equation. β″-Al 2 O 3 ceramics showed the best bending strength and ionic conductivity at 1550 °C when the doping amount of TiO 2 is 0.4 wt.% and 0.8 wt.%, respectively. [ABSTRACT FROM AUTHOR]

Due to its excellent ionic conductivity and electronic insulation, β/β″-alumina is widely used as a solid electrolyte in molten salt electrochemical cell and alkali metal thermoelectric convertor (AMTEC). In this article, nano-3mol% Yttrium partial stabilized zirconia (3YSZ) toughened β″-alumina solid electrolytes (BASEs) were fabricated by surface modification of β/β"-alumina precursor particles with ethylenediaminetetraacetic acid (EDTA) - Zirconium (IV)/Yttrium (III) complex. The performance of BASEs with 0-10 wt% amount of nano-3YSZ addition (Zr-BASE) was systematically investigated on their phase composition, density, microstructure, bending strength, and conductivity. It was found that nano-3YSZ grains were intergranular and uniformly distributed in BASE matrix even at as low as 3 wt% amount of addition, which resulted in higher density, more homogeneous microstructure, higher Weibull modulus, higher characteristic strength and increased grain boundary resistance of Zr-BASE than those of BASE without 3YSZ addition. Zr-BASE with 5 wt% amount of nano-3YSZ addition demonstrated good conductivity (0.071 S•cm−1 at 300 °C, 0.33 S cm−1 at 600 °C) and higher characteristic strength (283 MPa). The obtained results indicated that surface modification by EDTA-Zr(IV)/Y(III) complex advantaged in the preparation of better performance BASEs with a small amount of nano-3YSZ addition. Image 1 • EDTA complex surface modification was used to uniformly adding nano-3YSZ to BASE. • Zr-BASE was obtained with higher mechanical strength and medium ion conductivity. • BASE with 5 wt% 3YSZ addition showed better ion conductivity and mechanical strength. • EDTA complex was good at preparing better performance BASE with low 3YSZ addition. [ABSTRACT FROM AUTHOR]

• Nonaqueous HEMA-DEGDA gelation system is developed to form Li-BASE green body. • Plasticizer is successfully used to eliminate cracks and warpage in the green body. • Perfect gelcast of Li-BASE is obtained with mechanical strength of 17 MPa. • Sintered gelcast of Li-BASE exhibits good mechanical and electrical properties. A novel non-aqueous gelcasting system based on the polymerization of 2-hydroxyethyl methacrylate (HEMA) with low toxicity is applied to the fabrication of lithium stabilized beta alumina solid electrolyte (Li-BASE). Triethanolamine and polyethylene glycol (MW. 1000) are used as dispersant and plasticizer, respectively. Effects of dispersant concentration, solids loading and plasticizer concentration on the rheological behavior of the suspensions are investigated and optimized. Cracking and warpage phenomena in the gelcast green body during drying process are discussed. Green body gelcast from the optimized suspension shows homogeneous microstructure with a relative density of 59.4 % and a bending strength of 17 MPa. Properties, including the relative density, phase composition, microstructure, bending strength and ionic conductivity, of Li-BASEs sintered from green body formed by gelcasting and cold isostatic press are evaluated. Results show that gelcasting forming technique performs well in preparing BASE ceramics with high Weibull modulus and ionic conductivity. [ABSTRACT FROM AUTHOR]