Design and environmental security application of a cd(II) coordination polymer: Degradation and sensing of nitroaromatic compounds

The development of functional coordination polymer with photocatalytic capabilities has gained attention for environmental cleanup and security applications. Here, we reported the synthesis, structural characterization, and photocatalytic activity of a Cd(II) coordination polymer, [Cd(L)(Im)]n (H₂L = 4,4′-{(1,2-phenylenebis(methylene)bis(oxy)}dibenzoic acid and Im = Imidazole) (1), designed for the visible-light-driven degradation and sensing of nitro-aromatic compounds. CP 1 was synthesized hydrothermally using and characterized by single-crystal XRD, FT-IR, UV–Vis spectroscopy, PXRD, and TGA. Photocatalytic studies show that 1 effectively sensing of nitroaromatic compounds such as m-nitrophenol (MNP), sodium p-nitrophenol (SNP), and 4-nitrotoluene (PNT) at ppb levels, following pseudo-first-order kinetics. Mechanistic investigations suggest that superoxide radicals (O₂•-) play a key role in the degradation process. Additionally, recyclability tests confirm the material's stability and reusability. This work highlights the potential of Cd(II)-based coordination polymers as efficient and reusable photocatalysts for environmental and security applications.