resumo
A novel nonaqueous route was applied for the synthesis of rare earth phenylphosphonate hybrid nanostructures by reacting rare earth chlorides with phenylphosphonic acid in benzyl alcohol. Powder X-ray diffraction and transmission electron microscopy studies reveal the ordered lamellar structure, with an interlayer distance of 155 nm The rare earth phosphate layers are spaced by phenyl rings, which connect the hybrid structure by pi-pi interactions The composition, thermal behavior, and surface state were investigated It was found that the obtained hybrid materials are multiwavelength emitters due to the overlap of the UV/blue phenyl-related emission with the intra-4f(v) emission in the red and green for the Eu(3+)- rind Tb(3+)-doped hybrids, respectively We demonstrate that the phenylphosphonate hybrid nanostructures synthesized under nonaqueous conditions constitute a good host lot lanthanide ions (Ln(3+)) in terms of an efficient ligand-to-Ln(3+) sensitization For the case of the Eu(3+)-based hybrids, we also provide evidence that the nonaqueous synthesis route leads to the absence of water molecules within the first coordination sphere of Ln(3+) and, hence, to a significant increase of the absolute emission quantum yield (0 45) compared with those synthesized by the aqueous route (0 25). This work demonstrates the potential and advantage of nonaqueous routes for the synthesis of organic-inorganic hybrids, specifically, with respect to enhanced photoluminescent features
palavras-chave
ORGANIC-INORGANIC NANOCOMPOSITES; SOL-GEL ROUTES; LUMINESCENT PROPERTIES; OPTICAL-PROPERTIES; LANTHANIDE PHOSPHONATES; LAMELLAR NANOHYBRIDS; CRYSTAL-STRUCTURES; COMPLEXES; OXIDE; CHEMISTRY
categoria
Chemistry; Science & Technology - Other Topics; Materials Science
autores
Di, WH; Ferreira, RAS; Willinger, MG; Ren, XG; Pinna, N
nossos autores
Maria Rute de Amorim e Sá Ferreira André
Professor Catedrático
Nicola Pinna
InvestigadorProjectos
Functionalised Advanced Materials and Engineering of Hybrids and Ceramics - FAME (FAME)
Nanostructured Photoluminescent rare-earth nanotubes and microporous silicates (PTDC/CTM/73243/2006)
RMNE-UA-National Network of Electron Microscopy (REDE/1509/RME/2005 )
agradecimentos
This work was partially supported by the European Network of Excellence FAME and the WCU (World Class University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R3I-10013) and FCT projects (PTDC/CTM/73243/2006) and (REDE/1509/RME/2005). W.D. is grateful for the support of FCT (Grant No SFRH/BED/40881/2007).