HFCVD and CSVT techniques working together to produce nanostructured tungsten oxide

Hot Filament Chemical Vapour Deposition (HFCVD) was used to deposit tungsten oxide clusters on a graphite surface using a tungsten filament as source. These clusters were subsequently transported onto quartz and Si substrates where they transformed into WO3 − X nanowires. The transport of tungsten species from source to substrate was made through the Close Spaced Vapour Transport (CSVT) technique. The synthesized nanostructures were characterized by means of SEM, EDS, XRD techniques as well as by Raman spectroscopy. The results show that the nanowires have a monoclinic structure, a diameter about 100 nm and they were extended many tenths of micrometers.