Construction of a luminescent square-like Cd₆Eu₂ nanocluster for the quantitative detection of 2,6-dipicolinic acid as an anthrax biomarker

Abstract

Two Cd-Ln (Ln = Ho(III) and Eu(III)) complexes 1 and 2 were synthesized using two organic ligands. The square-like Cd6Eu2 nanocluster 2 exhibits luminescence response to DPA through the enhancement...

Rapid and Reliable Excitation Wavelength-Dependent Detection of 2,6-Dipicolinic Acid Based on a Luminescent Cd(II)–Tb(III) Nanocluster

“…Recently, we found that some Eu(III) complexes with Schiff base ligands could be used as fluorescent sensors to detect DPA. 23,24 A common method for the synthesis of metal clusters is the use of polydentate organic ligands bearing oxygen or hybrid oxygen−nitrogen donor atoms to bridge metal ions, for example, carboxylates, 25 alkoxides, 26 and phosphonates. 27 In our previous study, some 14-and 42metal nanoclusters containing pure 4f ions were constructed from polydentate vanillin-type ligands.…”

Enhancement of Emission and Negative Thermal Quenching Effect of Na2TiF6:Mn4+,TEAH+ by Antenna Effect of TEAH+

“…The reasons can be explained as follows: (a) It is improved by the antenna effect of TEAH + . That is, there is an effective intramolecular energy transfer from TEAH + to the activated Mn 4+ ions [21,22] . (b) The size of organic cations will directly affect the Mn−Mn spacing in inorganic blocks, and the increase of Mn−Mn spacing inhibits the energy transfer of Mn−Mn, then leads to the gradual enhancement of QY i [42–44] …”

“…That is, there is an effective intramolecular energy transfer from TEAH + to the activated Mn 4 + ions. [21,22] (b) The size of organic cations will directly affect the MnÀ Mn spacing in inorganic blocks, and the increase of MnÀ Mn spacing inhibits the energy transfer of MnÀ Mn, then leads to the gradual enhancement of QY i . [42][43][44] Influence of Mn 4 + and TEAH + concentrations on emission intensity…”

“…[20] It is reported that effective intramolecular energy transfer from organic ligands to the activated RE 3 + ions (RE = rare earth), called the antenna effect, can greatly enhance the photoluminescence emission of RE 3 + . [21,22] In addition, the luminescence of many organic-inorganic hybrid luminescent materials is also effectively enhanced by the antenna effect of organic compounds. [23][24][25][26][27] Therefore, it suggests that the antenna effect may be used to improve the luminescence or luminescent properties of Mn 4 + doped organic-inorganic hybrid fluoride phosphors.…”

“…It is reported that effective intramolecular energy transfer from organic ligands to the activated RE 3+ ions (RE=rare earth), called the antenna effect, can greatly enhance the photoluminescence emission of RE 3+ [21,22] . In addition, the luminescence of many organic‐inorganic hybrid luminescent materials is also effectively enhanced by the antenna effect of organic compounds [23–27] .…”