Flexible Ligand Based Lanthanide Three-Dimensional Metal-Organic Frameworks with Tunable Solid-State Photoluminescence and OH-Solvent-Sensing Properties

GERMÁN E. GOMEZ; ELENA V. BRUSAU; ANNA KACZMAREK; CAROLINE MELLOT-DRAZNIEKS; JOAQUÍN SACANELL; GWENAELLE ROUSSE; RIK VAN DEUN; CLÉMENT SANCHEZ; GRISELDA E. NARDA; GALO J. A. A. SOLER-ILLIA

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2017 vol. 2017 p. 2321 - 2331

1434-1948

Luminescent 3D metal-organic frameworks constructed by trivalent lanthanides (Nd3+, Sm3+, Eu3+, Gd3+, Tb3+) and a flexible ligand (2-methylsuccinate) (Ln-msucc) have been hydrothermally obtained as polycrystalline solids. They were fully characterized by X-ray powder diffraction, thermal analysis, vibrational spectroscopy and scanning electron microscopy. The crystalline structure and topological features were elucidated and compared with those of related Ln-MOFs. The magnetic studies reveal that Nd-msucc and Gd-msucc present antiferromagnetic and ferromagnetic behavior respectively. Moreover, the solid state photoluminescence properties (SSPL) of all the compounds were fully explored. Depending on the lanthanide content, these materials exhibited luminescence performances in near infrared and visible regions. Particularly, the photophysical behavior of the Eu phase was exhaustively examined and the radiative and non-radiative constants and intrinsic quantum yields were calculated. The hypersensitive nature of Eu³+ ⁵D₀→⁷F₂ transition allowed an in-depth study of the optical response in presence of various protic and aprotic solvents. As far as we know, the chemical-sensing studies employing Eu-msucc constitutes the first case reported for a lanthanide succinate-derived framework. The obtained results being promising for the elaboration of specific chemical sensors based on this material.