Sequential effects of two cations on the fluorescence emission of a coordination polymer with Zn 4 O core in node.

Autor: Sendh J; Department of Chemistry, Indian Institute of Technology Guwahati Guwahati-781 039 Assam India juba@iitg.ac.in +91-361-2582311., Baruah JB; Department of Chemistry, Indian Institute of Technology Guwahati Guwahati-781 039 Assam India juba@iitg.ac.in +91-361-2582311.
Jazyk: angličtina
Zdroj: RSC advances [RSC Adv] 2024 Oct 07; Vol. 14 (43), pp. 31598-31606. Date of Electronic Publication: 2024 Oct 07 (Print Publication: 2024).
DOI: 10.1039/d4ra06309k
Abstrakt: Distinct changes in the fluorescence emissions of free ligand 5-(1,3-dioxo-1 H -benzo[de]isoquinolin-2(3 H )-yl)isophthalic acid (H 2 NAPHISO) than a 2D-zinc-coordination polymer of it, caused by sequential interactions with different sets of binary cations were observed. The coordination polymer having unsymmetrical Zn 4 O core of tetranuclear zinc-node could be dispersed in dimethylformamide without its degradation. The coordination polymer had an emission peak at 435 nm (quantum yield = 0.082) which was selectively quenched by adding Fe 2+ ions. Based on this quenching, the Fe 2+ ions in aqueous solution could be detected with a detection limit 42.57 nM. The metal ions such as Li + , Na + , Cd 2+ , Hg 2+ , Al 3+ did not interfere in the detection; but each of these ions together with Fe 2+ ions showed characteristic shift of the emission spectra. The H 2 NAPHISO in dimethyl formamide was non-fluorescent, but showed emission at 452 nm upon addition of Cd 2+ or Zn 2+ ions. This new emission of H 2 NAPHISO caused by zinc or cadmium ions was not quenched by Fe 2+ ions. Various cations had affected the emission of the H 2 NAPHISO with Zn 2+ which was much different from the corresponding changes caused by the same ion on the emission of the coordination polymer. For example, the Mn 2+ and Zn 2+ ions together in a solution of the ligand showed a broad emission spectrum spreading over 380-450 nm, but ions Sn 2+ and Zn 2+ together had showed emission at a shorter wavelength (380 nm). These allowed to modulate the emission of the ligand by binary combination of metal ions.
Competing Interests: There is no conflict of interest to declare.
(This journal is © The Royal Society of Chemistry.)
Databáze: MEDLINE
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