New 3D Cd(II)-based pillar-supported metal − organic framework as fluorescent sensor for sensitive detection of agricultural pesticide pymetrozine

Abstract

A new three dimensional Cd(II)-based MOF with composition {Cd10(btc)8((bpp)4(Hbpp)4]·2bpp·H2O} (WAU-1) has been synthesized by reaction of Cd(II) salt with 1,3,5-benzenetricarboxylic acid (H3BTC) ligand and 2,5-bis(pyrid-4-yl)pyridine (bpp) co-ligand. The single crystal X-ray analysis showed that the WAU-1 shows 3D pillar-supported framework constructed by bpp co-ligands and [Cd3(btc)2] layers and exhibited typical 6-node pcu-like topology with the point symbol of{412.63}. The sensing studies have been performed on WAU-1 which suggested that the MOF can be used as highly sensitive fluorescent sensor to detect pymetrozine (PYM) a new class of pesticide through fluorescence quenching. Furthermore, the plausible fluorescence quenching mechanism which WAU-1 displayed against PYM and other insecticides has been proposed using theoretical calculations.