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
RTECS number	ZG3850000
Properties
Chemical formula	Y2O3
Molar mass	225.81 g/mol
Appearance	White solid.
Density	5.010 g/cm^3, 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).
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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

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

1. Yong-Nian Xu; Zhong-quan Gu; W. Y. Ching (1997). "Electronic, structural, and optical properties of crystalline yttria". Phys. Rev. B56 (23): 14993–15000. Bibcode:1997PhRvB..5614993X. doi:10.1103/PhysRevB.56.14993.
2. "Yttrium compounds (as Y)". Immediately Dangerous to Life and Health. National Institute for Occupational Safety and Health (NIOSH).
3. P. H. Klein and W. J. Croft (1967). "Thermal conductivity , Diffusivity, and Expansion of Y₂O₃, Y₃Al₅O₁₂, and LaF₃ in the Range 77-300 K". J. Appl. Phys. 38 (4): 1603. Bibcode:1967JAP....38.1603K. doi:10.1063/1.1709730.
4. J. Kong; D.Y.Tang; B. Zhao; J.Lu; K.Ueda; H.Yagi; T.Yanagitani (2005). "9.2-W diode-pumped Yb:Y₂O₃ ceramic laser". Applied Physics Letters 86 (16): 161116. Bibcode:2005ApPhL..86p1116K. doi:10.1063/1.1914958.
5. M.Tokurakawa; K.Takaichi; A.Shirakawa; K.Ueda; H.Yagi; T.Yanagitani; A.A. Kaminskii (2007). "Diode-pumped 188 fs mode-locked Yb³⁺:Y₂O₃ ceramic laser". Appl.Phys.Lett. 90 (7): 071101. Bibcode:2007ApPhL..90g1101T. doi:10.1063/1.2476385.
6. J.-F.Bisson; D.Kouznetsov; K.Ueda; S.T.Fredrich-Thornton; K.Petermann; G.Huber (2007). "Switching of emissivity and photoconductivity in highly doped Yb³⁺:Y₂O₃ and Lu₂O₃ ceramics". Appl.Phys.Lett. 90 (20): 201901. Bibcode:2007ApPhL..90t1901B. doi:10.1063/1.2739318.
7. Mindat, http://www.mindat.org/min-40471.html

External links

• Yttrium oxide information at Webelements.