Thin Solid Films, Vol.517, No.12, 3600-3605, 2009
A hot-wire chemical vapor deposition (HWCVD) method for metal oxide and their alloy nanowire arrays
A concept for synthesizing nanowire arrays of transition metal oxides and their alloys using hot wire chemical vapor deposition (HWCVD) is discussed. Here, unlike conventional HWCVD, the hot filaments act as the source of the metal for the synthesis of one dimensional nanostructures. In the present concept, the chemical vapor transport of metal oxides generated by heating the filaments in low amounts of oxygen, onto substrates maintained at lower temperatures leads to the formation of metal oxide nanowires. Experiments performed using tungsten and molybdenum filaments showed that the nucleation density of the resulting metal oxide nanowires could be varied by varying the substrate temperature. Experiments performed using a magnesium source inside the reactor, in addition to tungsten filaments, resulted in the formation Of MgWO(4) nanowires. This clearly indicates the possibility of either doping the metal oxide nanowires; or alloying during synthesis. (C) 2009 Elsevier B.V. All rights reserved.
Keywords:Metal oxides;Tungsten oxide;Molybdenum oxide;Nanowires;Nanotubes;Nucleation and growth mechanisms;Vapor-solid (VS) methods;Doping and absorption spectroscopy