Stable Lanthanide–Organic Framework Materials Constructed by a Triazolyl Carboxylate Ligand: Multifunction Detection and White Luminescence Tuning

Abstract

Under hydrothermal conditions, we have successfully synthesized six isostructural lanthanide coordination polymers, [LnL1.5(H2O)2]·1.75H2O (1–6; Ln = Eu, La, Pr, Nd, Sm, Gd), by the reaction of 5-methyl-1-(4-carboxylphenyl)-1H-1,2,3-triazole-4-carboxylic acid (H2L) and Ln­(NO3)3·6H2O. Structural analysis shows that polymers 1–6 show novel three-dimensional supramolecular network structures. The luminescent properties for polymer 1 have been investigated at room temperature. The results have shown that polymer 1 can be used as a chemical sensor for multifunctional testing such as UO2 2+, Fe3+ ion detection, and small organic molecule detection because of its strong fluorescence properties. In particular, polymer 1 exhibits extremely high selectivity and sensitivity for the detection of Fe3+ ions. In addition, white-light emission is achieved through a reasonable tuning proportion by mixing Gd3+ and Eu3+.

Design and properties of multiple-emitter luminescent metal–organic frameworks

“…Ln 3+ is the standard emissive metal type in multi-metal luminescent MOFs, also mostly by taking advantage of the antenna effect from organic linkers or ligands (Scheme 2). [44][45][46] The most straightforward and often optimal strategy for the preparation Scheme 2 Schematic diagram for an antenna effect (energy transfer) from ligands to Ln 3+ as well as the energy transfer process from Tb 3+ to Eu 3+ . of multi-emitter f-f heterometallic LMOFs is the introduction of one Ln 3+ as a co-emitter through doping into a homometallic lanthanide-LMOF.…”

Research Progress in the White Light-Emitting Lanthanide-Based Complex/Coordination Polymer Materials

“…另外, 该 课题组 [90] 在 H 2 L52 与 Al 3＋ 形成的 MOF 中封装 Eu 3＋ 及辅 助配体 TTA 之后得到白光聚合物材料, 并以此为 LED 芯片涂层制备了 WLED, 光色与理想白光几乎相同. 白 凤英 等 [91] 的近期工作同样证明, 白光可通过蓝光和红 光调制而成.…”

Mono- and Mixed Metal Complexes of Eu3+, Gd3+, and Tb3+ with a Diketone, Bearing Pyrazole Moiety and CHF2-Group: Structure, Color Tuning, and Kinetics of Energy Transfer between Lanthanide Ions

“…This is facilitated by both a profound understanding of the luminescence physics of monometallic compounds and diverse applications of MMLC. Such compounds exhibit properties of "luminescent thermometers" [44,45] and also can act as chemical sensors [10,46,47] and color-tunable emitting materials [48][49][50]. The relative proximity of the excited state energies of Eu 3+ (~17,240 cm er1 ) and Tb 3+ (~20,400 cm −1 ) and the relatively small metal-to-metal distances in most common structures [51] cannot only provide two independent luminescence processes for each of the ions but also allow the transfer of excitation energy from Tb 3+ ions to Eu 3+ .…”