A SIMPLE METHOD FOR THE SYNTHESIS OF TUNGSTEN TRIOXIDE NANORODS ARRAY WITHOUT CATALYST

Arrays of tungsten oxide nanorods, approximately 500 nm in diameter and 10 μm in length, have been grown in a catalyst-free reaction by heating tungsten wires at 900°C in a humid argon flow. They were systematically characterized using different surface analysis techniques. The chemical composition was determined to be stable stoichiometric binary oxide monoclinic tungsten trioxide. Water vapor was found to be crucial for the formation of these WO3 nanorods. The vapor–solid (VS) process was introduced to discuss the growth mechanism.