Dual-Function Lanthanide–Organic Frameworks Based on a Zwitterionic Ligand as a Ratiometric Thermometer and a Selective Sensor for Nitroaromatic Explosives
Ting Zhou, Shuang Liu, Song Wang, Shengyong Mi, Pan Gao, Xianmin Guo, Qijin Su, Huadong Guo
Abstract
Lanthanide–organic frameworks have been extensively exploited as efficient chemical sensors for versatile analyte detection. In this work, based on a zwitterionic ligand, N-(4-carboxybenzyl)-4-(4-carboxyphenyl)pyridinium chloride, a family of lanthanide–organic frameworks, [Ln2(L)3·NO3]·(NO3)2·xsolvent [Ln-MOF (Ln = Eu3+ and Tb3+)], has been synthesized and structurally characterized. The obtained Eu3+/Tb3+-mixed Tb99.9/Eu0.1-MOF can serve as a ratiometric thermometer with high sensitivity from 247 to 377 K. For its strong luminescence and good water stability, Eu-MOF can be developed as a selective and sensitive sensor for detecting the nitroaromatic explosive 2,4,6-trinitrophenol with a low detection limit of 82.35 nM.