Site-Dependent Tb3+Luminescence by Energy Transfer from Ce3+in Ce3+-Tb3+Codoped LaLuO3

Ce3+-Tb3+codoped LaLuO3was prepared by doping Tb3+site-selectively at a La or Lu site and doping Ce3+simultaneously at a Lasite. X-ray diffraction analysis revealed the expansion and contraction ofthe unit-cell volume according to the substituting sites of Ce3+and Tb3+,confirming the occupation of Ce3+at a La site and Tb3+at a La or Lu site.Photoluminescence due to energy transfer from Ce3+to Tb3+wasinvestigated by exciting the 4f-5d transition band of Ce3+. The site-dependent Tb3+luminescence spectra revealed that the energy transferoccurred from Ce3+to not only Tb3+at La sites but also Tb3+at Lu sites.Because Tb3+at both sites can show green luminescence by Ce3+4f-5dexcitation, as well as Tb3+4f-5d excitation, in Ce3+-Tb3+codopedLaLuO3, the excitation wavelength range for Tb3+luminescence waswidely extended up to 380 nm, which is attainable with near-UV LEDs.

Automated summary

Ce3+-Tb3+ codoped LaLuO3 was prepared by selectively doping Tb3+ at a La or Lu site and doping Ce3+ simultaneously at a La site. X-ray diffraction analysis confirmed the occupation of Ce3+ at a La site and Tb3+ at a La or Lu site, which resulted in the expansion and contraction of the unit-cell volume. Photoluminescence analysis showed that energy transfer occurred from Ce3+ to Tb3+ at both La and Lu sites, leading to the extension of the excitation wavelength range for Tb3+ luminescence in Ce3+-Tb3+ codoped LaLuO3.