Lanthanopolyoxometalates as Building Blocks for Multiwavelength Photoluminescent Organic-Inorganic Hybrid Materials

Organic-inorganic hybrid materials were prepared by combining lanthanide(III) substituted Wells-Dawson anions as inorganic building blocks and 3-hydroxypicolinate (picOH) as the organic ligand. The organic-inorganic hybrids obtained K-n[Ln(x)(alpha(2)-P2M17O61)(picOH)(7)]center dot yH(2)O (M-VI = W and Ln(III) = La, Ce, Sm, Eu, Tb, Er; or M-VI = Mo and Ln(III) = Eu) were characterized by chemical analysis and spectroscopic methods such as FTIR and FT-Raman, P-31 and C-13 MAS NMR spectroscopy. Photoluminescence measurements on the prepared hybrid materials were performed showing the intra-4f(N) emission in the visible (Eu-III, Tb-III compounds) and in the near-infrared (Er-III compound) spectral regions, being, in all the cases, sensitized by both the picOH ligand and the polyoxometalate moiety. A maximum quantum yield value of 0.18 was found for K-11[Eu-2(alpha(2)-P2Mo17O61)(picOH)(7)]center dot 10H(2)O. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)