Highly sensitive detection of tetracycline and Fe3+ and for visualizable sensing application based on a water-stable luminescent Tb-MOF

A Multifunctional CaII–EuIII Heterometallic Organic Framework with Sensing and Selective Adsorption in Water

“…The lifetime of CaEuCAM is quite longer than that of the Eu III compound based on CAM 3− , 56 and the quantum yield is better or comparable to those previously documented. [40][41][42][43][44][45][46][47][48]63,64,68 It is well documented that the presence of O−H oscillators (ν̃= 3600 cm −1 ) in water molecules 69 of the Eu III coordination sphere could produce a significant quenching in that four O−H oscillators, which are sufficient to induce a nonradiative deactivation of 5 D 0 . 69 However, in our case, a longer lifetime and larger quantum yield are obtained because the first Eu III coordination sphere is free of O−H oscillators, as discussed in the structural analysis.…”

“…In this context, metal–organic frameworks (MOFs) are believed to be one of the promising materials for diminishing these challenges as a result of their noteworthy structural features like high surface area and wide range of pore environment modulation, which could favor host–guest supramolecular interactions. − However, some concerns, especially signal-to-noise ratio and chemical/water stability, should also be taken into account before application. Attributed to the featured emissions of Ln III , luminescent Ln-MOFs with characteristic emission, large Stokes shifts, long luminescence lifetimes, and high quantum yields, on the one hand, have become efficient sensing platforms for heavy metal ions and nitroaromatics with a high signal-to-noise ratio, high selectivity, sensitivity, and fast response in recent years. − Upon thorough literature search, several Ln-MOFs are obtained for Fe 3+ and 3-NP detection, however, their detection limits mostly stay at the micromolar level, and highly efficient sensors with low nanomolar levels are rare . On the other hand, Ln-MOFs could be good adsorbing materials for organic dyes due to their large specific surface area, tunable pore sizes, designable channels, active sites on the organic linker, and charge characteristics. ,, Notably, heterometallic Ln III -containing systems with amazing structural features and multifunctional performance are highly desirable due to the complementary and synergistic effects on the electronic and space of different metal centers. − Compared to numerous documented 3d-4f heterometallic MOFs, Ln-MOFs incorporated with alkaline earth metals are still in their infancy. − Ln-MOFs merged with inexpensive, readily available, and environmentally friendly alkaline earth metal ions are particularly promising .…”

Metal-organic frameworks as photocatalysts in energetic and environmental applications

“…High surface area, structural designability, tunable pore channels, high surface-to-volume ratios, flexibility to be functionalized with different ligands and metal centers which can be extended up to 90% of the crystal volume, and rich compositions are just a few of the extraordinary features of MOFs structures [ 8 – 11 ]. These distinctive characteristics depict MOFs as porous network architectures, which have drawn significant research interest in a number of potential application areas, including gas storage [ 12 ], separation [ 13 ], drug delivery [ 14 ], sensing [ 15 ], nonlinear optics [ 21 ], luminosity [ 22 ], heterogeneous catalysis [ 23 ], photocatalysis [ 24 ], and carbon capture and transformation [ 25 , 26 ].…”

Optical chemosensors based on metal organic frameworks for selective detection of hazardous pollutants: A review

“…Furthermore, the detection limit for Fe 3+ is 0.78 μM, 7.73 × 103 M −1 . The high luminescence quenching effect was attributable to the competitive energy absorption process, which causes the great sensitivity and selectivity [135] .…”