화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.153, No.4, H78-H81, 2006
Synthesis of Ca4GdO(BO3)(3): Eu3+, Al3+ by sol-gel processing and its luminescence properties
Single phase of Eu3+ and Al3+ codoped Ca4GdO(BO3)(3) was successfully prepared by sol-gel processing at 1000 degrees C, which is 400 degrees C lower than that of solid-state reaction. Morphology analysis reveals that the synthesized phosphors have nonagglomerated, uniform, small particle size and sphere-like morphology without the grinding process. The photoluminescence properties of Eu3+ and Al3+ activated Ca4GdO(BO3)(3) phosphor prepared by sol-gel processing under UV and vacuum-UV excitation were studied and compared to the bulk synthesized by solid-state reaction. The broad bands centered at about 181 and 248 nm were obtained in their excitation spectra, which are assigned to the absorption of the host crystal and the charge transition (CT) band of Eu3+. The broad band at about 135-160 nm was observed in this phosphor for the first time. By calculating, the broad band about 135-160 nm could be assigned to the CT band and f-d transition of Gd3+. The excitation intensity was enhanced by codoping with Al3+ into the Ca4GdO(BO3)(3):Eu3+ lattices. Under 254- and 147-nm excitation, the intense pure red emission (lambda(em)=612 nm) was observed in their emission spectra and the sample prepared by the sol-gel process had higher luminescence intensity than that derived from solid-state reaction.