Two Stable Zn (II) Coordination Polymers as Dual‐Functional Luminescent Sensors for Efficient Detection of Nitrofurazone, Pefloxacin, and Cr₂O₇²⁻ in Water

ABSTRACT Two new Zn (II) coordination polymers, {[Zn (OBA)(L)]·H 2 O} n ( 1 ) and {[Zn 2 (TCPA) 2 (L) 2 ]·H 2 O} n ( 2 ), were synthesized under hydrothermal condition. Here, L = 2‐(1 H ‐imidazol‐1‐yl)methyl)‐5,6‐dimethyl‐1 H ‐benzo[ d ]imidazole, H 2 OBA = 4,4′‐dicarboxydiphenyl ether, H 2 TCPA = tetrachloroterephthalic acid. Structural analyses revealed that 1 exhibits a 2D hcb topology of {6 3 } while 2 displays a four‐connected 2D sql layer with the point symbol of {4 4 .6 2 }. Both 1 and 2 are extended to 3D supramolecular frameworks through hydrogen bonding interactions. These CPs demonstrate remarkable thermal and chemical stability across a wide pH range of 3 to 12. Notably, they can serve as dual‐functional luminescent sensors for the sensitive, selective, and recyclable detection of nitrofurazone (NFZ)/Cr 2 O 7 2− ions (for 1 ) and pefloxacin (PEF)/Cr 2 O 7 2− ions (for 2 ) in aqueous solutions. The limits of detection (LODs) of 1 towards NFZ and Cr 2 O 7 2− ions are 2.20 × 10 −7 and 4.90 × 10 −7 mol·L −1 , respectively. For 2 , the LOD is 5.42 × 10 −8 mol·L −1 for PEF and 3.40 × 10 −7 mol·L −1 for Cr 2 O 7 2− ions. It is worth noting that this is the first report of luminescent Zn (II)‐CPs based on L ligands for the sensing of NFZ, PEF, and Cr 2 O 7 2− ions. And the quenching mechanism was deeply investigated.