In this article, hierarchical flower-like ZnO nanostructures with controlled morphology and dimensions have been synthesized by solution phase approach and functionalized by Au nanoparticles (AuNPs) with the combination of electrodeposition to explore novel applications. The photocatalytic activity and lithium storage capacity of these hybrid nanostructures have been investigated. It has been found that hybrid nanostructure combining the large specific surface area, stability and catalytic activity of small AuNPs, demonstrate the higher photocatalytic activity than that of pure ZnO. Furthermore, an initial discharge capacity of 1280 mA h g À1 and a reversible capacity over 392 mA h g À1 at the 50 cycles are achieved for the Au-ZnO hybrid nanostructure, which is found to be much better than that of any previously reported ZnO anodes. The improved lithium storage capacity and cycle life of the Au-ZnO electrode result from the Li activity of Au-ZnO phase. The photocatalytic and electrochemical activity of Au-ZnO hybrid nanostructures provide a new platform for energy storage, environmental remediation and photocatalysis applications.

Carbon-coated silicon nanowire array films prepared by metal catalytic etching of silicon wafers and pyrolyzing of carbon aerogel were used for lithium-ion battery anodes. The films exhibited an excellent first discharge capacity of 3344 mAh g−1 with a Coulombic efficiency of 84% at a rate of 150 mA g−1 between 2 and 0.02 V and a significantly enhanced cycling performance, i.e., a reversible capacity of 1326 mAh g−1 was retained after 40 cycles. These improvements were attributed to the uniform and continuous carbon coatings, which increased electronic contact and conduction and buffered large volume changes during lithium ion insertion/extraction.

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Nitrogen-enriched porous carbon nanofiber networks (NPCNFs) were successfully prepared by using lowcost melamine and polyacrylonitrile as precursors via electrospinning followed by carbonization and NH 3 treatments. The NPCNFs exhibited inter-connected nanofibrous morphology with a large specific surface area, well-developed microporous structure, relatively high-level nitrogen doping and great amount of pyridinic nitrogen. As free-standing new anode materials in lithium-ion batteries (LIBs), the NPCNFs showed ultrahigh capacity, good cycle performance and superior rate capability with a reversible capacity of as high as 1323 mA h g À1 at a current density of 50 mA g À1 . These attractive characteristics make the NPCNFs materials very promising anode candidates for high-performance LIBs and, as free-standing electrode materials to be used in other energy conversion and storage devices.

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