Dual-emitting barium based metal-organic nanosheets as a potential sensor for temperature and anthrax biomarkers

Abstract

The development of novel 2D materials, due to the promising applications they have enabled through their unique properties, has attracted increasingly more research interest. In this regard, novel dual-emitting coordination polymer nanosheets were developed by doping Eu 3+ and Tb 3+ ions into the nanostructures of the [Ba(DPA) 2 (H 2 O) 2 ] n (DPA=dipicolinic acid) coordination polymer (BCP). Single crystal x-ray crystallography revealed that BCP is a 1D coordination polymer and its three-dimensional supramolecular architecture is constructed with a relatively strong hydrogen bonding in the ac crystallographic plane and weak non-covalent interactions along the b axis. Using energetic ultrasound irradiations, synthesis of nanoscale BCP along with the unzipping of the weak interactions between the ac layers was accomplished. The resulting BCP nanosheets was used as the host lattice and was doped with Eu 3+ and Tb 3+ ions. Remarkably, the sensing ability of both Eu 3+ and Tb 3+ doped coordination polymer (Ln@BCP) nanosheets towards temperature and the DPA anthrax biomarker were investigate. The high relative sensitivity value of 2.42% K −1 and their reusability, makes Ln@BCP nanosheets an ideal candidate for the nanothermometry. They also exhibited high selective detection characteristics towards the DPA anthrax biomarker with a 0.03 nM detection limit. Therefore, Ln@BCP nanosheets can also be considered as an efficient multi-responsive optical sensor.

Highly Selective Chloromethanes Detection Based on Quartz Crystal Microbalance Gas Sensors with Ba-MOFs

“…As stated in the crystal structure, the coordination numbers of all Ba 2+ ions in 1 and 2 are 10, while the coordination numbers of the four Ba 2+ ions in 3 are 8, 9, 10, and 9 (Table S5), and all the Ba 2+ ions in 1 – 3 have water molecules involved in the coordination. To our knowledge, the highest coordination number of Ba 2+ is 10, − and chloromethanes possess the ability to dissociate the solvent coordination bonds and coordinate with hard metal ions. , So 1 and 2 with high selectivity to chloromethanes are mainly due to the exchange of coordination water molecules with CH 2 Cl 2 , CHCl 3 , and CCl 4 and possible electrostatic effects between (CH 3 NH 3 ) + cations and chloromethanes with more electronegative chlorine atoms.…”

Two-Dimensional Metal-Organic Framework Materials: Synthesis, Structures, Properties and Applications

“…The intense intensity at lower temperature is ascribed to the rigidified framework, allowing rapid intersystem crossing process to restrict the energy loss via non-radiative decay . Other interesting temperature sensors based on Cu–I clusters, heterometallic lanthanide centers, and other related systems are also reported. ,− …”

Monolayer nanosheets formed by liquid exfoliation of charge-assisted hydrogen-bonded frameworks

“…An array of 2D hydrogen-bonded materials on surfaces have also been demonstrated using a variety of building motifs, though these are not free-standing. 36,37 We are only aware of a few examples of "top-down" formation of nanosheets containing hydrogenbonds within the layers, but in these examples hydrogenbonds are only formed in one dimension and co-ordination bonds, 38 covalent bonds, 39 or pi-stacking, 40 hold the nanosheets together in the other. To our knowledge there are no examples of nanosheets connected in two-dimensions exclusively through strong hydrogen-bonding interactions.…”