Molecular spectra of a D-π-A typed polydentate ligand chromophore and its simultaneous response to trace Cu2+ and Co2

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 220; p. 117130
• Main Authors: Hu, Lei, Yin, Liwen, Wang, Fang, Yu, Dehua, Wang, Chenshu, Hui, Mingwei, Chu, Luyao, Zhu, Xiao, Yan, Zhengquan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.09.2019
• Subjects: D-π-A polydentate ligand; Simultaneous sensing; Trace Co2; Trace Cu2; UV–vis spectrum; Trace Cu2; Simultaneous sensing; D-π-A polydentate ligand; Trace Co2; UV–vis spectrum
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2019.05.035

A D-π-A conjugated polydentate ligand chromophore, N-8′-quinolyl-2,4,6- trihydroxyl benzamide (NQTB), was identified and synthesized using tri-hydroxyl phenol as donated-electron group, N-heterocycle quinoline as accepted-electron one and CN bond as bridged one. It was expected to chelate some heavy metal ions with prominent colorimetric or spectral changes. After its UV–vis absorption spectrum was investigated in detail, it was noted that NQTB possessed excellent spectral recognition ability to Cu2+ and Co2+ from other coexisting ions in aqueous. Under the optimized conditions, NQTB could simultaneously discriminate trace Cu2+ and Co2+ in environmental aqueous samples with low detection limits (1.9 × 10−8 mol/L and 5.7 × 10−8 mol/L) and satisfying analytical precisions (R.S.D. ≤3.3% and ≤2.6%) respectively. The sensing mechanism was confirmed to form some stable 5-membered-co-6-membered condensed rings between Cu2+/Co2+ and O/N atoms in NQTB. [Display omitted] •A D-π-A typed polydentate chromophore N-8′-quinolyl-2,4,6-trihydroxyl benzamide was developed.•Its UV-vis spectral response to metal ions depended on tested conditions.•A potential spectral method for simultaneous sensing trace Cu2+ and Co2+ was developed•The sensing mechanism was confirmed to form stable 5-membered-co-6- membered condensed rings