A dual functional 1D Cd-based coordination polymer for the highly luminescent sensitive detection of Fe³⁺ and picric acid

Fluorescent coordination polymers have drawn extensive attention in sensing applications. Herein, we report a carbazole-based one-dimensional coordination polymer [CdL(H₂O)(DMF)₂]·DMF (CdL, H₂L = 9H-carbazole-2,7-dicarboxylic acid, DMF = N,N-dimethylformamide). In CdL, each Cd²⁺ ion is four-bridged by carboxylates, which is further linked by the carbazole units to form a one-dimensional Cd–O–C chains along the c-axis. CdL displays high water stability in the pH range of 3–10. Luminescence experiments indicate that CdL could selectively detect Fe³⁺ during the concentration range of 0–0.1 mm in water with a K_sv of 8022 m⁻¹ and picric acid (PA) within the concentration range of 0–0.05 mm in methanol solution with a K_sv of 17948 m⁻¹ respectively. The above results reveal that CdL can be applied as a multiresponse luminescence sensor for selectively sensing for Fe³⁺ in water and PA in methanol solution.