Very large area, uniform TiO 2 @carbon composite nanofibers were easily prepared by thermal pyrolysis and oxidization of electrospun titanium(IV) isopropoxide/polyacrylonitrile (PAN) nanofibers in argon. The composite nanostructures exhibit the unique feature of having TiO 2 nanocrystals encapsulated inside a porous carbon matrix. The unique orderly-bonded nanostructure, porous characteristics, and highly conductive carbon matrix favour excellent electrochemical performance of the TiO 2 @carbon nanofiber electrode. The TiO 2 @carbon hybrid nanofibers exhibited highly reversible capacity of 206 mAh g À1 up to 100 cycles at current density of 30 mA g À1 and excellent cycling stability, indicating that the composite is a promising anode candidate for Li-ion batteries.

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The decomposition properties of Mg(BH 4 ) 2 -LiNH 2 mixtures were investigated. Apparent NH 3 release appeared from 50 to 300 °C for the Mg(BH 4 ) 2 -LiNH 2 mixtures with mole ratios of 1:1.5, 1:2, and 1:3, while only hydrogen release was detected for the mixture with a mole ratio of 1:1. In the case of the Mg(BH 4 ) 2 -LiNH 2 (1:1) sample, the onset of the first-step dehydrogenation starts at 160 °C, with a weight loss of 7.2 wt % at ∼300 °C, which is improved significantly compared to the pure Mg(BH 4 ) 2 alone. From Kissinger's method, the activation energy, E a , for the first and second step dehydrogenation in Mg(BH 4 ) 2 -LiNH 2 (1:1) was estimated to be about 121.7 and 236.6 kJ mol -1 , respectively. The improved dehydrogenation in the combined system may be ascribed to a combination reaction between [BH 4 ] and [NH 2 ], resulting in the formation of Li-Mg alloy and amorphous B-N compound.

TiO 2 (B)@SnO 2 core-shell hybrid nanowires have been synthesized by a facile hydrothermal process and subsequent liquid phase reaction. Hybrid nanowire electrodes exhibit excellent reversible lithium storage capacity rate capability and good cyclability, mainly due to the particular architecture of the composite, which features an open continuous channel along its axis, facilitating lithium ion diffusion, and provides effective mechanical support for the TiO 2 (B) core, alleviating the stress produced during discharge-charge cycling and also preventing the pulverization of the Sn nanoparticles. Owing to its superior electrochemical performance, this composite could be a promising potential anode material for lithium ion batteries.

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Highly uniform, relatively large area TiO2/SnO 2/carbon hybrid nanofibers were synthesized by a simple method based on thermal pyrolysis and oxidation of an as-spun titanium-tin/polyacrylonitrile nanoweb composite in an argon atmosphere. This novel composite features the uniform dispersion and encapsulation of highly uniform nanoscale TiO 2/SnO2 crystals in a porous carbon matrix. The high porosity of the nanofiber composite material, together with the conductive carbon matrix, enhanced the electrochemical performance of the TiO 2/SnO2/carbon nanofiber electrode. The TiO 2/SnO2/carbon nanofiber electrode displays a reversible capacity of 442.8 mA h g-1 for up to 100 cycles, and exhibits excellent rate capability. The results indicate that the composite could be a promising anode candidate for lithium ion batteries. Keywordshybrid, carbon, sno2, performance, highly, uniform, tio2, storage, lithium, enhanced, greatly, nanofibers Disciplines Engineering | Physical Sciences and Mathematics Publication DetailsYang, Z., Meng, Q., Guo, Z., Yu, X., Guo, T. and Zeng, R. (2013

Carbon nanotubes (CNTs)/MnOx-Carbon hybrid nanofibers have been successfully synthesized by the combination of a liquid chemical redox reaction (LCRR) and a subsequent carbonization heat treatment. The nanostructures exhibit a unique one-dimensional core/shell architecture, with one-dimensional CNTs encapsulated inside and a MnOx-carbon composite nanoparticle layer on the outside. The particular porous characteristics with many meso/micro holes/pores, the highly conductive one-dimensional CNT core, as well as the encapsulating carbon matrix on the outside of the MnOx nanoparticles, lead to excellent electrochemical performance of the electrode. The CNTs/MnOx-Carbon hybrid nanofibers exhibit a high initial reversible capacity of 762.9 mAhg−1, a high reversible specific capacity of 560.5 mAhg−1 after 100 cycles, and excellent cycling stability and rate capability, with specific capacity of 396.2 mAhg−1 when cycled at the current density of 1000 mAg−1, indicating that the CNTs/MnOx-Carbon hybrid nanofibers are a promising anode candidate for Li-ion batteries.