A ratiometric fluorescent probe based on a dual-ligand lanthanide metal–organic framework (MOF) for sensitive detection of aluminium and fluoride ions in river and tap water

Abstract

In this work, we report a ratiometric fluorescence probe towards Al3+ and F- using lanthanide Metal−Organic Framework material, Eu-BDC-NH2/TDA, which is composed of a metal centre Eu3+, BDC-NH2 and TDA...

Facile synthesis of a fluorescent probe based on a terbium-based metal–organic framework for selective detection of Fe(iii) and Al(iii)

“…Due to the energy mismatch between the ligand and Al 3+ , the increase of π* → π energy transfer of the ligand led to the enhanced fluorescence. 47–49 Several previous studies also reported similar phenomena and results. 50,51…”

Eu3+-MOF fluorescence sensor based on a dual-ligand strategy for visualised detection of an anthrax biomarker 2,6-pyridine dicarboxylic acid

“…Our previous work also supports this viewpoint. 23 The energy gap (ΔE) between Eu 3+ and triplet-state energy (T1) of BDC-NH 2 is lower than 2500 cm −1 , which is the minimum energy range for effective sensitisation. 35,36 Whereas, the ΔE between Eu 3+ and T1 of TDA matches the optimal energy level required for ligand-to-metal charge transfer (LMCT) process.…”

Dual-Functional Eu–Metal–Organic Framework with Ratiometric Fluorescent Broad-Spectrum Sensing of Benzophenone-like Ultraviolet Filters and High Proton Conduction

“…To prepare ratiometric fluorescent sensors, the constructed materials need to produce double/multiple emission peaks. Lanthanide-based metal–organic frameworks (Ln–MOFs) have been used broadly in the preparation of ratiometric fluorescent sensing materials, which have been applied to the detection of ions, temperature, pH, biomolecules, etc. − Ln–MOFs can be used to prepare ratiometric sensors primarily depending on their modulated “antenna effect”. − The degree of energy transfer between ligand and Ln 3+ directly affects whether the emission peaks of ligand and Ln 3+ ions can appear simultaneously. Therefore, the selection of appropriate ligands is the key to constructing Ln–MOFs with dual-emission peaks. − According to Latva’s rule, the Eu 3+ ion can be effectively sensitized when the energy gap between the 5 D 0 state of the Eu 3+ ion and the triplet state (T 1 ) of the ligand is in the range of 2500–4000 cm –1 .…”