Crystallization and optical properties of Eu2+: CsCaCl3 nanocrystals in glasses

Narrow-band blue luminescence materials are desirable in full color display with wide color gamut. Divalent rare earth europium doped luminescence materials show excellent optical properties as promising backlit materials in display. However, narrow-band blue luminescence materials are still lacking. Herein, novel blue emitting Eu2+: CsCaCl3 NCs are precipitated in the glasses, and effects of EuCl3 doping concentration and heat-treatment conditions on the growth behavior and optical properties of Eu2+: CsCaCl3 NCs precipitated in glasses are investigated. Doping concentration of EuCl3 in glass and the heat-treatment condition can effectively regulate the Eu2+/Eu3+ molar ratio in glasses, size of Eu2+: CsCaCl3 NCs, and effective doping concentration of Eu2+ ions in CsCaCl3 NCs formed in the glasses. Besides, effect of phase separation on glass transmittance is explored to improve the glass optical properties. Upon incorporation of Eu2+ ions into CsCaCl3 NCs in glasses, blue photoluminescence at 435 nm with full width at half maximum of 22 nm and color purity of ∼97.2 % is realized, and concomitantly, photoluminescence lifetimes are extended and quantum efficiency are significantly improved. These results demonstrate that Eu2+: CsCaCl3 NCs doped glasses are promising blue emitting materials.