Immobilized dyes within anionic indium coordination polymer for photocatalytic 1O2 generation

A new anionic indium coordination polymer, (Me2NH2)[In(OH-BDC)(2)]center dot H2O (1), has been designed and synthesized under solvothermal conditions based on organic ligand 5-hydroxyisophthalic acid. 1 exhibits a 2D layered structure with rhombic windows, which is stacked to form 3D supramolecular network by the pi-pi stacking interactions of phenyl rings of ligand in adjacent layers. It not only shows excellent resistance to acid or basic conditions but also has good tolerance to various common solvents. Moreover, due to the negative charge of the host framework, it shows remarkable selective adsorption for positive charge dyes such as methylene blue (MB), rhodamine B (RhB) and crystal violet (CV), and the removal rates are higher than 90%. In particular, the adsorption capability of 1 to RhB is higher than most CPs based adsorbents. In addition, MB@1 is a high-efficiency reactive oxygen species (ROS) producer with good photocatalytic activity for the oxidation of 1,5-dihydroxynaphthalene (1,5-DHN) and can be recycled five times without loss of activity. To our knowledge, it is the first time that dye@CP was used for ROS production and photooxidation of 1,5-DHN.