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A new facile approach to fabricate carbon decorated Si nanotubes (C@SiNTs) was proposed by using chemical vapor deposition. The as-synthesized C@SiNTs structure revealed excellent electrochemical performance as an anode in lithium ion batteries (LIBs), which delivered a gravimetric capacity as high as 2085 mA h g−1 at 0.2 C rate, and capacity retention of 95% after 200 cycles relative to the capacity value in the 10th cycle. Even the current density increased to 20 C, 421 mA h g−1 specific capacity can still be achieved. Such high specific capacity, excellent cyclability, and rate performance could be attributed to the hollow structure of Si nanotubes, which can effectively accommodate the strain caused during the Li+ uptake and release processes. Meanwhile, the decorated carbon nanoparticles effectively improved the electrical conductivity of the whole electrode which can further improve the specific capacity. The results exhibited here pave a new way to synthesize different Si architectures for high robust and scalable Si-based anodes for lithium ion batteries.

Biocompatible polynorepinephrine based particles with excellent biocompatibility for efficient delivery of therapeutics to cancer cells.

We report a facile strategy to coaxially grow compact SnO 2 over-layers on multiwall carbon nanotubes (MWCNTs) with hierarchical structures and controlled thickness via a hydrothermal method, using NaF as a morphology controlling and directing agent. The thickness of the SnO 2 over-layers can be controlled from several tens of nanometers down to several nanometers by adjusting the ratio of carbon nanotubes to Sn precursor. When applied as anode materials for lithium ion batteries, carbon nanotubes with coaxially grown thin (~10 nm) SnO 2 over-layers showed lithium storage performance with a reversible capacity of 431 mA h g −1 after 50 cycles, which is two times better than that of thick (~55 nm) SnO 2 over-layers or mixtures of carbon nanotubes and separated SnO 2 nanoparticles. The improved cyclic performance was attributed to reduced agglomeration, enhanced electronic conductivity and released internal strain during the lithium insertion/extraction.

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