Two silver(I) complexes based on dicarboxylate and flexible bis(benzimidazole) ligands: synthesis, crystal structures, sensing and photocatalytic properties

Two Ag(I) complexes, namely [Ag2(L1)2(HMIP)2·H2O]n (1) and [Ag2(L2)2(HPA)2]n (2) (L1 = 1,6-bis(2-methylbenzimidazol-1-yl)hexane, L2 = 1,6-bis(benzimidazol-1-yl)hexane, H2MIP = 5-methylisophthalic acid, H2PA = phthalic acid), were hydrothermally synthesized and characterized by physicochemical and spectroscopic methods. 1 Processes a binuclear Ag(I) structure which is further extended into a 2D supramolecular network by hydrogen bonds and π–π stacking interactions. 2 Features a 1D meandering chain which is linked into a 3D supramolecular network by Ag···O and π–π stacking interactions. Complex 1  is shown to be a highly sensitive material for luminescence detecting Fe3+ in aqueous solution. These complexes display high photocatalytic activities for degradation of methylene blue under UV irradiation.