A method of producing networks of low melting
metal oxides such as crystalline
gallium oxide comprised of one-dimensional nanostructures. Because of the unique arrangement of wires, these crystalline networks defined as “nanowebs”, “
nanowire networks”, and / or “two-dimensional nanowires”. Nanowebs contain wire densities on the order of 109 / cm2. A possible mechanism for the fast self-
assembly of crystalline
metal oxide nanowires involves multiple
nucleation and coalescence via oxidation-reduction reactions at the
molecular level. The
preferential growth of nanowires parallel to the substrate enables them to coalesce into regular polygonal networks. The individual segments of the polygonal network consist of both nanowires and nanotubules of β-
gallium oxide. The synthesis of highly crystalline noncatalytic low melting metals such as β-
gallium oxide tubes, nanowires, and nanopaintbrushes is accomplished using molten gallium and
microwave plasma containing a mixture of monoatomic
oxygen and
hydrogen.
Gallium oxide nanowires were 20-100 nm thick and tens to hundreds of microns long.
Transmission electron microscopy (TEM) revealed the nanowires to be highly crystalline and devoid of any structural defects. Results showed that multiple
nucleation and growth of
gallium oxide nanostructures can occur directly out of molten gallium exposed to appropriate composition of
hydrogen and
oxygen in the
gas phase. The method of producing nanowebs is extendible to other low melting metals and their oxides such as for example:
zinc oxide,
tin oxide, aluminum oxide,
bismuth oxide, and
titanium dioxide.