Two new Ag (I) supramolecular complexes based on melamine: Synthesis, structures and photocatalytic activity under visible light irradiation

Two new supramolecular complexes [Ag 2 (MA) 2 (2-nbd)]·2.5H 2 O ( 1 ) and [Ag 2 (MA) 2 (3-npa)]·2H 2 O ( 2 ) (2-H 2 nbd   =   2-nitroterephthalic acid; MA   =   melamine; 3-H 2 npa   =   3-nitrophthalic acid) have been synthesized under ultrasound conditions and characterized by infrared spectra (IR), thermogravimetric analysis (TGA), elemental analyses (EA) and X-ray diffraction (XRD). Complex 1 exhibits 2D framework through the bridging of carboxylic acid ligand and melamine ligand. Complex 2 presents a binuclear silver structural unit, which was further construct to three-dimension structure via hydrogen-bond interaction. The photocatalytic performance and photoluminescent properties of them were also investigated. And the results show that complex 1 and 2 exhibited good photocatalytic activity towards the degradation of Rhodamine B (RhB) and Methylene Blue (MB) under visible light irradiation. Moreover, it is verified that the degradation rate fits the first-order kinetics.