A novel 1-D chain organic–inorganic hybrid CuII–PrIII heterometallic germanomolybdate decorated by 2-picolinic acid ligands

Abstract

A novel 1-D chain organic–inorganic hybrid CuII–PrIII heterometallic germanomolybdate decorated by 2-picolinic acid ligands [NH4]2[Pr(H2O)5]2[Cu(pic)2]2[Cu(pic)2(H2O)2]3[α- GeMo12O40]2·24H2O (1) [Hpic = 2-picolinic acid] has been obtained via the strategy of combining in-situ assembly reaction and stepwise synthesis in aqueous solution and structurally characterized by IR spectra, elemental analyses, single-crystal X-ray diffraction, and thermogravimetric analysis. It should be pointed out that the polyoxoanion unit of 1 consists of two plenary Keggin [α-GeMo12O40]4− anion and an organic–inorganic hybrid 3d–4f heterometallic {[Pr(H2O)5]2[Cu(pic)2]2[Cu(pic)2(H2O)2]3}6+ segment and neighboring polyoxoanion units are further expanded into a 1-D chain alignment by virtue of {Cu(pic)2} linkers. Furthermore, the absorption properties of 1 toward the cationic dye methylene blue (MB) in water solution have been investigated in detail, which shows a good absorption capacity toward the dye in aqueous solution and the absorption kinetic conforms to the second-order kinetic model.