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Two lanthanide doped nanosystems Ca0.8Ln0.1Na0.1WO4 (Ln = Eu, Sm), denoted as Eu@CWO and Sm@CWO, were prepared by a "top-down" approach in three simple steps: activation, miniaturization by high-energy milling, and further calcination. The solids were thoroughly characterized by X-ray powder diffraction (XRPD) and Scanning-electron microscopy (SEM). Also, analyses of the structure of the compounds and the impact of milling on the crystallite shape and size were carried out through Rietveld refinements. Solid-state photoluminescence was studied in terms of excitation, emission, lifetimes (τobs) and europium-quantum yields. Finally, the Eu@CWO sample was employed as a potential water-stable chemical sensor towards toxic cations, showing a quenching effect in the presence of iron ions. [ABSTRACT FROM AUTHOR]

The intense development that Metal‐Organic Frameworks have experienced along the last two decades, reflects the interest on these compounds as a new generation of multifunctional materials with diverse applications. The first works of Prof. Omar Yaghi devoted to obtain open frameworks by combining rigid aromatic linkers and a variety of metal centers, encouraged the creativity of the scientific community to designcoordination polymers employing aliphatic ligands as multitopic building blocks. Here, a revision of the literature dedicated to rare earth coordination networks mainly based in succinate ligand and derivatives is performed. A structural analysis of 2D and 3D frameworks based on rare earth elements and succinate, was carried out considering their inner connectivities and topologies with focus on those compounds with potential photoluminescent and catalytic technological applications. Thus, a variety of optical behaviours regarding the emission mechanisms, colours, lifetimes, quantum yields as well as chemical/thermal sensing properties are presented and compared with related phases found in literature. The catalytic performance of several rare earth‐succinates in three important reactions is discussed in terms of their acidity, dimensionality and available active centers towards the formation of the desired products analysing parameters such as selectivity, yields and TOFs. [ABSTRACT FROM AUTHOR]

Luminescent 3D metal-organic frameworks (MOFs) constructed from 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 of all the compounds were fully explored. Depending on the lanthanide content, these materials exhibited luminescence in the near-infrared and visible regions. In particular, the photophysical behavior of the Eu phase was exhaustively examined and the radiative and nonradiative constants and intrinsic quantum yields were calculated. The hypersensitive nature of the Eu3+ 5D0→7F2 transition allowed an in-depth study of the optical response in the presence of various protic and aprotic solvents. As far as we know, the chemical-sensing studies employing Eu-msucc constitute the first case reported for a lanthanide succinate-derived framework. The obtained results are promising for the elaboration of specific chemical sensors based on this material. [ABSTRACT FROM AUTHOR]