Europium Oxide, Europium Sesquioxide, Europia, 1308-96-9

Europium Oxide, Europium Sesquioxide, Europia, 1308-96-9

Europium(III) oxide overview

Europium(III) oxide (Eu₂O₃) is a high-value rare earth oxide prized for its role as the standard red-emitting dopant in modern phosphors. It combines thermal stability with well-defined optical transitions of Eu³⁺, making it essential in lighting, display technologies, and specialty optics.

Chemical identity

• Chemical name: Europium(III) oxide

• Formula: Eu₂O₃

• Molecular weight: 351.93 g/mol

• CAS number: 1308-96-9

• EC number: 215-164-2

• Appearance: Pinkish-white powder

• Crystal structure: Cubic and monoclinic polymorphs (phase depends on synthesis/thermal history)

• Density: ~7.4 g/cm³

• Melting point: ~2,350 °C

• Solubility: Insoluble in water; dissolves in strong acids to form Eu(III) salts

Physical and chemical characteristics

• Optical behavior: Eu³⁺ exhibits sharp f–f transitions; dominant red emission (~611 nm, ⁵D₀ → ⁷F₂) in suitable hosts, with high color purity.

• Magnetic behavior: Weakly paramagnetic.

• Thermal stability: High melting point and phase stability for use in high-temperature processes.

• Chemical reactivity: Stable in air; converts to europium salts (e.g., nitrates, chlorides) upon acid treatment.

• Particle engineering: Available from nano to micronized grades; morphology and surface area tailored for dispersion and sintering.

Production and grades

• Feedstocks: Rare earth concentrates (e.g., bastnäsite, monazite) after REE separation.

• Typical route: Acid leaching → solvent extraction/ion exchange → precipitation (hydroxide/carbonate) → calcination to Eu₂O₃ → milling/classification.

• Purity grades:

  • Technical: 99.9% (3N) for ceramics/general use

  • High-purity: 99.99–99.999% (4N–5N) for phosphors, LEDs, and advanced optics

• Forms: Nano-grade, submicron, micronized powders; agglomerate-controlled, low-chloride/sulfate variants for electronic applications.

Applications and mechanisms

• Phosphors and displays:

  • Red phosphors: Eu₂O₃ is the principal Eu³⁺ source to dope host lattices (e.g., Y₂O₃:Eu, oxynitrides), delivering vivid red emission for LEDs, fluorescent lamps, and display screens.

  • Color calibration: High chromatic purity and stability under operating temperatures.

• Optical materials:

  • Specialty glasses/ceramics: Improves luminescent properties; used where controlled red emission or upconversion is required.

  • Laser/host precursors: Eu-doped hosts for research-grade lasers and sensing.

• Electronics:

  • Luminescent devices and sensors: Eu³⁺ transitions enable robust optical markers; used in anti-counterfeiting pigments and sensing films.

  • Semiconductor research: As a dopant or interfacial layer in niche thin-film systems.

• Ceramics and pigments:

  • Color additives: Pink/red hues in ceramics and enamels; stable coloration under firing.

• Nuclear and materials science:

  • Isotopic properties: Europium isotopes have notable neutron cross-sections; oxide form is more a precursor than a direct absorber in reactors.

Procurement specifications (ERP-ready)

• Purity: 3N/4N/5N with declared total REE and trace metals (Fe, Si, Ca, Al, Na, Pb, Cu).

• Particle size distribution: D10/D50/D90; sieve residue; agglomerate level.

• BET surface area: Critical for phosphor blending and sintering behavior.

• Loss on ignition (LOI): Indicates hydroxide/carbonate residues and adsorbed moisture.

• Phase purity: XRD-confirmed Eu₂O₃; absence of oxychlorides/oxynitrides unless specified.

• Residual anions: Low chloride/sulfate for electronic/optical applications.

• Color and whiteness: L, a, b* reporting for consistency in pigments/phosphors.

• Packaging: Moisture-barrier, antistatic for nano grades; batch/lot traceability.

Safety, handling, and storage

• Toxicity: Low acute toxicity; fine powders may irritate eyes/respiratory tract.

• Protective equipment: Gloves, safety glasses, and suitable dust masks (FFP2/FFP3 for nano/submicron powders).

• Storage: Keep dry, sealed; avoid humidity to minimize surface hydroxylation and agglomeration.

• Waste: Dispose of rare earth oxides per local regulations; avoid release to water systems.

Synonyms

• Europium Oxide

• Europium(III) Oxide

• Europium Sesquioxide

• Europia

• Eu₂O₃