Sonochemical synthesis of two nano-sized nickel(II) coordination polymers derived from flexible bis(benzimidazole) and isophthalic acid ligands

Abstract

Two new Ni(II) coordination polymers (CPs), [Ni(L1)(IPA)]n (1) and [Ni(L2)(IPA)·H2O]n (2) (L1 = 1,6-bis(benzimidazol-1-yl)hexane, L2 = 1,6-bis(5,6-dimethylbenzimidazol-1-yl)hexane, H2IPA = isophthalic acid) were synthesized by hydrothermal and sonochemical process. X-ray crystal structure analysis revealed that 1 possesses a 4-connected 3D architecture with a 65.8 CdSO4 topology, while 2 exhibits a 2D layer, which can be classified as a honeycomb 63-hcb network. The results indicate that Ni(II) mixed CPs structurally modulated by the flexible bis(benzimidazole)-involved co-ligands. The role of ultrasound irradiation power, reaction time and reaction temperature on the size and morphology of the nano-sized 1 and 2 were investigated in detail. Further, fluorescence and photocatalytic activities of nano-sized CPs for degradation of methylene blue (MB) are presented.