resumo
In this manuscript, microwave-assisted synthesis was used to prepare a new organic building block and a Metal-Organic Framework based on this unit. The tetrapodal organic linker [1,1'-biphenyl]-3,3',5,5'-tetrayltetrakis(phosphonic acid) (H(8)btp) was combined with lanthanide cations affording the isotypical 2D lanthanide-organic frameworks [Ln(4)(H(6)btp)(2)(H(4)btp)(2)(H(8)btp)(H2O)(16)]center dot 12H(2)O [where Ln(3+) = La3+ (1), (La0.9Eu0.1)(3+) (2) and (La-0.9)(3+) (3)]. 1 was isolated as large single-crystals and its crystal structure was solved by single-crystal X-ray diffraction. Phase identification of the Eu3+-(2) and Tb3+-based (3) materials was performed by powder X-ray diffraction. Compound 1 consists of two-dimensional double-deck layers, characterized by an unprecedented tetranodal 2,4,4,4-connected layered network, with total point symbol {4-8(5))(2){4(2).8(4)}{4(3).8(2).10}(4)(4}(2). Supramolecular pi-pi interactions exist both within and between layers. 1-3 were fully characterized in the solid-state by a plethora of techniques [elemental and thermogravimetric analyses, electron microscopy (SEM and EDS), FT-IR spectroscopy and solid-state NMR]. Photoluminescence properties of the optically-active mixed-lanthanide materials 2 and 3 reveal that the employed H(8-x)btp(-x) residues are better suited to sensitize Tb3+ than Eu3+, with the measured lifetimes being of 0.83 +/- 0.01 and 0.22 +/- 0.01 ms, respectively. (C) 2016 Elsevier B.V. All rights reserved.
palavras-chave
ASSISTED SOLVOTHERMAL SYNTHESIS; BUILDING-BLOCK; MOFS; CATALYSIS; LIGAND; PYRENE; ACID)
categoria
Chemistry
autores
Firmino, ADG; Mendes, RF; Ananias, D; Vilela, SMF; Carlos, LD; Tome, JPC; Rocha, J; Paz, FAA
nossos autores
Ana Daniela Gonçalves Firmino
Investigador
Duarte Ananias
Investigador Auxiliar
Filipe Alexandre Almeida Paz
Investigador Principal
João Rocha
Prof. Catedrático
Luís Carlos
Professor Catedrático
Ricardo Faria Mendes
Investigador Júnior
Sérgio Manuel Felipe Vilela
Bolseiro de pós-Doutoramentoagradecimentos
Funding agencies and projects: We wish to thank Fundacao para a Ciencia e a Tecnologia (FCT, Portugal), the European Union, QREN, FEDER through Programa Operacional Factores de Competitividade (COMPETE), CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), CQE (Ref. FCT UID/QUI/0100/2013) and QOPNA (FCT UID/QUI/00062/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. We also thank FCT for funding the R&D project FCOMP-01-0124-FEDER-041282 (Ref. FCT EXPL/CTM-NAN/0013/2013).; Individual grants and scholarships: FCT is also gratefully acknowledged for the Ph.D. grants Nos. SFRH/BD/84495/2012 and SFRH/BD/84231/2012 (to ADF and RFM, respectively), and the post-doctoral research grants Nos. SFRH/BPD/94381/2013 and SFRH/BPD/95032/2013 (to SMFV and DA, respectively).