Four new silver-based complexes constructed from 3-nitrophthalic acid and pyrazine-like ligands: Syntheses, crystal structures and photodegradation activities

Abstract

Four Ag-based coordination polymers, Ag4(H2O)2(npth)2 (1), Ag4(epyz)2(npth)2 (2), [Ag(pyz)(Hnpth)]·H2O (3) and Ag(epyz)0.5(Hnpth) (4) (H2npth=3-nitrophthalic acid, pyz=pyrazine, epyz=2,3,5,6-tetramethylpyrazine), have been synthesized by ultrasonic or hydrothermal reactions of Ag(I) salts with H2npth and various pyrazine derivatives ligands. Compound 1 presents a 2D 44-sql network with Ag4 units, and compound 2 features novel cage-like Ag8 SBUs (secondary building unit), which are linked by epyz ligands to form a 3D framework. Compound 3 shows a 1D chain and compound 4 exhibits a 2D coordination polymer construction. The photocatalytic properties for the degradation of organic dye molecules have been examined, and the experiments show that compound 3 has a good degradation effect to Rhodamine B.