Farger Pierre, Leuvrey Cédric, Gallart Mathieu, Gilliot Pierre, Rogez Guillaume, Rocha João, Ananias Duarte, Rabu Pierre, Delahaye Emilie
Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504, F-67034 Strasbourg Cedex 2, France.
Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal.
Beilstein J Nanotechnol. 2018 Oct 30;9:2775-2787. doi: 10.3762/bjnano.9.259. eCollection 2018.
The synthesis and characterization of six new lanthanide networks [Ln(L)(ox)(HO)] with Ln = Eu, Gd, Tb, Dy, Ho and Yb is reported. They were synthesized by solvo-ionothermal reaction of lanthanide nitrate Ln(NO)·HO with the 1,3-bis(carboxymethyl)imidazolium [HL] ligand and oxalic acid (Hox) in a water/ethanol solution. The crystal structure of these compounds has been solved on single crystals and the magnetic and luminescent properties have been investigated relying on intrinsic properties of the lanthanide ions. The synthetic strategy has been extended to mixed lanthanide networks leading to four isostructural networks of formula [Tb Eu (L)(ox)(HO)] with = 0.01, 0.03, 0.05 and 0.10. These materials were assessed as luminescent ratiometric thermometers based on the emission intensities of ligand, Tb and Eu. The best sensitivities were obtained using the ratio between the emission intensities of Eu (D→F transition) and of the ligand as the thermometric parameter. [TbEu(L)(ox)(HO)] was found to be one of the best thermometers among lanthanide-bearing coordination polymers and metal-organic frameworks, operative in the physiological range with a maximum sensitivity of 1.38%·K at 340 K.
报道了六种新型镧系元素网络化合物[Ln(L)(ox)(H₂O)]（其中Ln = Eu、Gd、Tb、Dy、Ho和Yb）的合成与表征。它们是通过硝酸镧Ln(NO₃)₃·6H₂O与1,3 - 双(羧甲基)咪唑鎓[HL]配体以及草酸(H₂ox)在水/乙醇溶液中进行溶剂热离子热反应合成的。这些化合物的晶体结构已通过单晶解析，并且基于镧系离子的固有性质对其磁性和发光性质进行了研究。合成策略已扩展到混合镧系元素网络，得到了四种化学式为[Tb₁₋ₓEuₓ(L)(ox)(H₂O)]（x = 0.01、0.03、0.05和0.10）的同构网络。基于配体、Tb和Eu的发射强度，将这些材料评估为发光比率温度计。使用Eu（⁵D₀→⁷F₂跃迁）与配体的发射强度之比作为测温参数时，获得了最佳灵敏度。[Tb₀.₉Eu₀.₁(L)(ox)(H₂O)]被发现是含镧系元素的配位聚合物和金属有机框架中最佳温度计之一，在生理温度范围内有效，在340 K时最大灵敏度为1.38%·K⁻¹。
