Morphological Characterization of Tungsten Trioxide Nanopowders Synthesized by Sol-Gel Modified Pechini's Method

WO3 powders were first prepared by calcination of resin precursor at 550ºC under various initial concentrations of metal ion (12.5-50 mmol), acid (125-500 mmol), a complexing agent (32-262 mmol), and polyethylene glycol (1-16.5 mmol) in the air atmosphere.

The products were characterized using X-ray powder diffraction, field emission scanning electron microscopy, and energy dispersive spectroscopy. The results revealed that the WO3 nanopowders prepared with different amounts of chelating agent and polyethylene glycol, crystallized in monoclinic phase. The nanopowders were impurity-free due to the presence of the complexing agent and polyethylene glycol as carbon sources.