To increase the energy storage density of lithium-ion batteries, silicon anodes have been explored due to their high capacity. One of the main challenges for silicon anodes are large volume variations during the lithiation processes. Recently, several high-performance schemes have been demonstrated with increased life cycles utilizing nanomaterials such as nanoparticles, nanowires, and thin films. However, a method that allows the large-scale production of silicon anodes remains to be demonstrated. Herein, we address this question by suggesting new scalable nanomaterial-based anodes. Si nanoparticles were grown on nanographite flakes by aerogel fabrication route from Si powder and nanographite mixture using polyvinyl alcohol (PVA). This silicon-nanographite aerogel electrode has stable specific capacity even at high current rates and exhibit good cyclic stability. The specific capacity is 455 mAh g−1 for 200th cycles with a coulombic efficiency of 97% at a current density 100 mA g−1.

Ultrafast high‐temperature sintering (UHS) is a novel sintering technique with ultrashort firing cycles (e.g., a few tens of seconds). The feasibility of UHS has been validated on several ceramics and metals; however, its potential in consolidating glass–ceramics has not yet been demonstrated. In this work, an optimized carbon‐free UHS was utilized to prepare ZrO2–SiO2 nanocrystalline glass–ceramics (NCGCs). The phase composition, grain size, densification behavior, and microstructures of NCGCs prepared by UHS were investigated and compared with those of samples sintered by pressureless sintering. Results showed that NCGCs with a high relative density (～95%) can be obtained within ～50 s discharge time by UHS. The UHS processing not only hindered the formation of ZrSiO4 and cristobalite but also enhanced the stabilization of t‐ZrO2. Meanwhile, owing to the ultrashort firing cycles, the UHS technology allowed the NCGCs to be consolidated in a far from equilibrium state. The NCGCs showed a microstructure of spherical monocrystalline ZrO2 nanocrystallites embedded in an amorphous SiO2 matrix.

In this work, an aerodynamic levitation technology (ALT) was utilized to prepare ZrO2‐SiO2 glass‐ceramics with two different ZrO2 contents, that is, 35 mol% and 50 mol%. The glass‐ceramics were partially melted at ∼2000°C or fully melted at ∼3000°C by ALT, followed by rapid quenching to obtain spherical glass‐ceramic beads. The phase compositions and microstructures of the glass‐ceramics were characterized. Crystallization of ZrO2 occurred during the solidification process and ZrO2 content, processing temperature, and the addition of yttrium (3 mol%) affected the crystalline phase of ZrO2. No ZrSiO4 or crystalline SiO2 were formed during the solidification process and the glass‐ceramics were away from thermodynamic equilibrium due to rapid quenching. The glass‐ceramics showed a microstructure of irregular‐shaped ZrO2 micro‐aggregates embedded in an amorphous SiO2 matrix, with lamellar twins and lattice defects formed within ZrO2 crystals. For samples prepared at ∼3000°C, a liquid‐liquid phase separation occurred in the melt, which eventually resulted in the formation of large and irregular‐shaped ZrO2 aggregates. In comparison, for samples prepared at ∼2000°C, pre‐existed ZrO2 crystals formed during heating acted as nucleation sites during the cooling process, followed by grain growth to form large ZrO2 aggregates. Solidification and microstructure formation mechanisms were proposed to elucidate the solidification process during rapid cooling and the microstructure of the glass‐ceramics obtained.

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