Photoluminescent Properties and Local Structure of Tb Doped Fibrous Alumina

摘要： A boehmite sol which contains uniform ?brous nanoparticles has a unique property to form a ?lm by its self-assembling properties. When Tb ions were added to the sol, the ?lm became photoluminescent (PL) and emitted bright green light due to the f-f transition of Tb by UV irradiation. The PL intensity varied with calcination temperature during pretreatment. The best performance was obtained when the sample was treated around 800 °C. The PL performance normalized by the Tb content was higher for samples with a lower Tb content. Structural analysis by TEM, XRD, and XAFS revealed that when the Tb content was lower than Tb/Al = 2.5/97.5 in the atomic ratio, Tb ions were dispersed on the alumina surface isolated from each other, and those Tb species showed a high PL performance. On the other hand, for densely Tb doped samples, excessive Tb ions aggregated and formed Tb oxide nanoparticles, which were supposed to have lower PL e?ciencies.