Yttrium(III) oxide

Yttrium(III) oxide

Names
IUPAC name Yttrium(III) oxide.
Other names Yttria, diyttrium trioxide, yttrium sesquioxide
Identifiers
CAS Number	1314-36-9 Y
ECHA InfoCard	100.013.849
RTECS number	ZG3850000
Properties
Chemical formula	Y2O3
Molar mass	225.81 g/mol
Appearance	White solid.
Density	5.010 g/cm3, solid
Melting point	2,425 °C (4,397 °F; 2,698 K)
Boiling point	4,300 °C (7,770 °F; 4,570 K)
Solubility in water	insoluble
Solubility in alcohol acid	soluble
Structure
Crystal structure	Cubic (bixbyite), cI80[1]
Space group	Ia-3, No. 206
Coordination geometry	Octahedral
Hazards
EU classification (DSD)	None listed.
R-phrases	Not hazardous
S-phrases	S24/25
Lethal dose or concentration (LD, LC):
LDLo (lowest published)	>10,000 mg/kg (rat, oral) >6000 mg/kg (mouse, oral)[2]
Related compounds
Other cations	Scandium(III) oxide, Lanthanum(III) oxide
Related compounds	Yttrium barium copper oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

Yttrium oxide, also known as yttria, is Y₂O₃. It is an air-stable, white solid substance. Yttrium oxide is used as a common starting material for both materials science as well as inorganic compounds.

Uses

Gas Lighting

The original use of the mineral yttria and the purpose of its extraction from mineral sources was as part of the process of making gas mantles and other products for turning the flames of artificially-produced gases (initially hydrogen, later coal gas, paraffin, or other products) into human-visible light. This use is almost obsolete - thorium and cerium oxides are larger components of such products these days.

Materials science

It is the most important yttrium compound and is widely used to make Eu:YVO₄ and Eu:Y₂O₃ phosphors that give the red color in color TV picture tubes. Yttrium oxide is also used to make yttrium iron garnets, which are very effective microwave filters.

Y₂O₃ is used to make the high temperature superconductor YBa₂Cu₃O₇, known as "1-2-3" to indicate the ratio of the metal constituents:

2 Y₂O₃ + 8 BaO + 12 CuO + O₂ → 4 YBa₂Cu₃O₇

This synthesis is typically conducted at 800 °C.

The thermal conductivity of yttrium oxide is 27 W/(m·K).^[3]

Inorganic synthesis

Yttrium oxide is an important starting point for inorganic compounds. For organometallic chemistry it is converted to YCl₃ in a reaction with concentrated hydrochloric acid and ammonium chloride.

Lasers

Y₂O₃ is a prospective solid-state laser material. In particular, lasers with ytterbium as dopant allow the efficient operation both in continuous operation^[4] and in pulsed regimes.^[5] At high concentration of excitations (of order of 1%) and poor cooling, the quenching of emission at laser frequency and avalanche broadband emission takes place.^[6]

Natural occurrence

Yttriaite-(Y), approved as a new mineral species in 2010, is the natural form of yttria. It is exceedingly rare, occurring as inclusions in native tungsten particles in a placer deposit of the Bol’shaja Pol’ja river, Prepolar Ural, Siberia. As a chemical component of other minerals, the oxide yttria was first isolated in 1789 by Johan Gadolin, from rare-earth minerals in a mine at the Swedish town of Ytterby, near Stockholm.^[7]

References

External links

• Yttrium oxide information at Webelements.