New Cu(II)-based three dimensional supramolecular coordination polymer as photocatalyst for the degradation of methylene blue

Abstract

A new Cu(II)-based coordination polymer [Cu2(HL)2(bib)2] (1) has been synthesized by reacting two flexible linkers viz. 5-(4ˊ-carboxylphenoxy)isophthalic acid (H3L) and 1,1′-(1,4-butanediyl)bis(imidazole) (bib) a N-donor auxiliary ligand with CuSO4 under solvothermal condition. The single crystal X-ray analysis indicates that 1 possess 2D layered network, which further extends into 3D supramolecular framework through hydrogen bonding interactions. The coordination polymer 1 has been used as photocatalyst for the sustainable degradation of model aromatic dyes viz. methylene blue (MB), Rhodamine B (Rh B) and methylene orange (MO). The experiments demonstrate that 1 exhibits recyclable and better photocatalytic activity for photodegradation of MB (62.96%) than Rhodamine B (Rh B) and methylene orange (MO) in time span of 100 min. Furthermore, trapping experiments using scavengers indicate that hydroxyl radicals are the main species responsible for photocatalytic degradation of MB. Apart from this computational investigation has been executed to propose the plausible mechanism of photocatalysis.