Hierarchically designed SiOx /SiOy rolled-up bilayer nanomembranes are used as anodes for lithium-ion batteries. The functionalities of the SiO(x,y) layers can be engineered by simply controlling the oxygen content, resulting in anodes that exhibit a reversible capacity of about 1300 mA h g(-1) with an excellent stability of over 100 cycles, as well as a good rate capability.

Conformally carbon-coated FeP (FeP@C) nanoplates with abundant inner mesopores exhibit an extremely superior electrochemical performance for lithium-ion batteries.

Tape-shaped pitch fibers with a transverse cross-sectional size of 400 m width and ~30 m thickness, melt-spun from mesophase pitch, were adopted as a model for treatment in oxygen using various temperatures and durations to investigate their stabilization behavior. Several characterization techniques were used to systematically analyze the functional group species, oxygen content and distribution, local composition, thermal pyrolysis behavior and micro-structural changes in the various stabilized tapes. After oxidative stabilization treatment, the tape-shaped fiber exhibits uniform shrinkage behavior during subsequent heat treatments thereby maintaining its * Corresponding author. E-mail address: xkli8524@sina.com (X. Li) 2 tape shape and structural integrity. The ~30 m thick tapes can be stabilized completely by treatment in oxygen at 220 °C for ~10 h and this indicates a high efficiency of stabilization, which is, perhaps unexpectedly, higher than that of corresponding ~30 m diameter round-shaped fibers. Thermal decomposition pathways varied with the degree of stabilization and have obvious effects on the microstructure of the resulted tapes, which in turn strongly influences their final physical properties. Pitch tapes oxidized under mild conditions offered relatively higher mechanical performance. Tensile strength and Young's modulus of 2500 °C graphitized tapes, previously oxidatively stabilized at 220 °C for 20 h, were measured to be about 2 and 250 GPa, respectively.

The formation and growth of silicon carbide whiskers (SiCw)

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