Preparation method of tungsten oxide and metallic tungsten nano-powders using degreased cotton

Abstract

A simple method for producing nanopowders of tungsten oxides and metallic tungsten using degreased
cotton is proposed. Ammonium tungstate NH4W12O40 was used as a precursor. A medical cotton wool
was chosen for experiment. Structural characterizations of nanopowders were performed using X-ray
diffraction (XRD) and Raman spectroscopy. Raman Spectra was obtained by NTegra Spectra (NT-MDT),
where the light source is blue laser ̴ 473 nm. Analyses of XRD spectra showed that nanopowders have a
monoclinic structure. The morphology of synthesized nanopowders was studied using scanning electron
microscopy (SEM). The size of nanocrystals was estimated with Scherrer’s formula. The effect of
annealing temperature on nanoparticle sizes was investigated. The Raman spectra of the obtained samples
were studied as a function of the synthesis temperature. In the Raman spectra, broading and red shift of
the Raman bands with decreasing size are observed. The most pronounced Raman peaks are assigned to
the characteristic vibrations according to the available structural data.