Yellow tungsten oxide is a tungsten oxide which molecular formula is WO3. Its colors vary from its particle sizes. When the crystal size is about 1.5 um, it is yellow. When the crystal size is about 15 um, it is green. The appearances are different, but the characteristics are similar. Yellow tungsten oxide has many uses in our daily life. It is often used to product fireproof fabric of X ray screen phosphor, gas sensor and tungstate. Because of its bright yellow, yellow tungsten oxide is also used as a pigment in paints and ceramics.
Scanning electron microscope (SEM) is a kind of scanning equipment used for micrograph by multiplying objects, which can be metal, powder, etc. From the following SEM micrographs, the morphology structures are obviously different with different synthesis methods.