3D functional hetero-nanostructures of vertically anchored metal oxide nanowire arrays on porous graphene substrates

Mesoporous three dimensional hierarchical structure of copper oxide nanowires vertically anchored on graphene substrate was synthesized by a facile and green ‘alkali mediated synthesis’ under microwave irradiation. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Brunauer−Emmett−Teller surface area tests showed highly crystalline nanowires vertically anchored on porous graphene to give a unique mesoporous, hierarchical nanostructures. When applied as anode in lithium ion batteries, our materials exhibit capacity of 770 mAh g−1 even after 100 cycles with a Columbic efficiency in excess of 97%, reflecting the ability of the hierarchical network to accommodate the extreme volume changes of metal anodes that occur during the lithiation/delithiation reactions. The utility of our newly developed to synthesize anisotropic titania nano-wires or zinc oxide nano-flowers on graphene substrate is also reported.