Oxide Powder

Holmium III oxide, or holmium oxide is a chemical compound of a rare-earth element holmium and oxygen with the formula Ho2O3. Together with dysprosium(III) oxide (Dy2O3) holmium oxide is one of the most powerfully paramagnetic substances known. The oxide, also called holmia, occurs as a component of the related erbium oxide mineral called erbia.

Holmium III Oxide is a highly insoluble thermally stable Holmium source suitable for glass, optic and ceramic applications. Holmium oxide occurs in small quantities in the minerals monazite, gadolinite, and in other rare-earth minerals. Holmium metal easily oxidizes in air; therefore the presence of holmium in nature is synonymous with that of holmium oxide.

Holmium III oxide is one of the colorants used for cubic zirconia and glass, providing yellow or red coloring. Glass containing holmium oxide and holmium oxide solutions (usually in perchloric acid) has sharp optical absorption peaks in the spectral range 200-900 nm. They are therefore used as a calibration standard for optical spectrophotometers and are available commercially.

As most other oxides of rare-earth elements, holmium III oxide is used as a specialty catalyst, phosphor and a laser material. Holmium laser operates at wavelength of about 2.08 micrometres, either in pulsed or continuous regime. This laser is eye safe and is used in medicine, LIDARs, wind velocity measurements and atmosphere monitoring.

Holmium III oxide has some fairly dramatic color changes depending on the lighting conditions. In daylight, it is a tannish yellow color. Under trichromatic light, it is a fiery orange red, almost indistinguishable from the way erbium oxide looks under this same lighting. This is related to the sharp emission bands of the phosphors. Holmium oxide has a wide band gap of 5.3 eVand thus should appear colorless. The yellow color originates from abundant lattice defects (such as oxygen vacancies) and is related to internal transitions at the Ho3+ ions.