A regenerable zinc(II) coordination polymer as a dual-luminescent sensor for detection of Cr2O72– and 2,4,6-trinitrophenol in aqueous phase

Developing a fast and sensitive method for the detection of 2,4,6-trinitrophenol (TNP) or Cr2O72– in aqueous solution has received great attention. In this work, a regenerable fluorescent coordination polymer [Zn(L)(H2L)]n (1) has been successfully constructed using a novel Schiff base ligand N'-[(E)-(3,5-dibromo-2-hydroxyphenyl)methylene]isonicotinohydrazide(H2L) and exploited as a dual detection probe for the selective sensing of Cr2O72– and TNP in water media. Competitive fluorometric experiments involving mixtures of anions or nitro compounds demonstrated 1 as an efficient and selective sensor for both Cr2O72– and TNP. The limits of detection for Cr2O72– and 2,4,6-trinitrophenol in aqueous solutions were found to be 11.4 and 1.19 μM, respectively. Moreover, 1 can detect TNP and Cr2O72– in real water samples. All these features clearly demonstrate its great potential of practical TNP and Cr2O72– detection in water media for public safety and security.