A series of inorganic–organic hybrid cadmium borates with novel Cd-centred [Cd@B14O20(OH)6]2− clusters†
Abstract
Four novel inorganic–organic hybrid cadmium borates, namely [EAH]2{(py)2Cd@[B14O20−(OH)6]} (1, py = pyridine, EA = ethylamine), [PAH]2{(py)2Cd@[B14O20(OH)6]} (2, PA = propylamine), [pyH]2{(py)2Cd@[B14O20(OH)6]} (3) and {(AImH)2Cd@[B14O20(OH)6]} (4, AIm = 1-(3-aminopropyl)imidazole) have been solvothermally synthesized and characterized by elemental analysis, thermogravimetric analysis, IR spectroscopy, UV-Vis-NIR spectroscopy, fluorescence spectroscopy, powder X-ray diffraction, and single-crystal X-ray diffraction, respectively. They represent the first hybrid cadmium borates that exhibit 3D supramolecular open-frameworks with different topologies. All the networks are formed by the unprecedented Cd-centred cluster [Cd@B14O20(OH)6]2−, and further link each other via a multipoint H-bond system. UV-Vis-NIR spectral investigation reveals that these borates are wide-band-gap semiconductors. Moreover, they display strong fluorescence emission around 430 nm, making them excellent candidates for optoelectronic applications as blue materials.