Photoluminescent Porous Alginate Hybrid Materials Containing Lanthanide Ions

Department of Physics, CICECO, University of Aveiro, Portugal, Institut Charles Gerhardt-Montpellier, Materiaux Avances Pour la Catalyse et la Sante, UMR5253 CNRS-ENSCM-UM2-UM1, 8 rue de l'Ecole Normale, 34296 Montpellier, France.
Biomacromolecules (Impact Factor: 5.75). 08/2008; 9(7):1945-50. DOI: 10.1021/bm8002122
Source: PubMed


The photoluminescence features of Eu(3+)-, Tb(3+)-, Tb(3+)/Eu(3+)-alginate aerogel (hydrogel and alcogel) and Eu(3+)-alginate xerogel hybrids were investigated. The Eu(3+)-alginate aerogel and alcogel exhibit the highest (5)D0 quantum efficiencies (9.9 and 8.2%, respectively), while the hydrogel and xerogel have lower values (5.2 and 5.6%, respectively). The Tb(3+)/Eu(3+) hybrids are multiwavelength emitters in which the emission color can be tuned across the chromaticity diagram from the red toward the yellowish-green spectral regions, crossing the white area by selecting the excitation wavelength.

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