Three new aluminoborates: from 1D tube to 3D framework.

Three new aluminoborates (ABOs) KCs[Al{BO(OH)}{BO(OH)} (1), KCs[Al{BO}{BO(OH)}] (2), and Cs[Al{BO}{BO(OH)}] (3) have been made under solvothermal conditions. 1 features a 1D tube constructed by the alternation of [BO(OH)] clusters and AlO units, onto which the [BO(OH)] triangles are grafted. To further construct higher dimensional structures based on the structure 1, solvents were adjusted for high basicity, resulting in the formations of the 3D ABO frameworks 2 and 3. 2 and 3 are isostructural and built from [BO] clusters, AlO tetrahedra and [BO(OH)] triangles, in which [BO] clusters are bridged by AlO tetrahedra to produce a 2D ABO layer with 14-membered ring (MR) windows, and the [BO(OH)] triangles act as the linkers to bridge the adjacent ABO layers to form 3D ABO frameworks containing eight types of channels. UV-vis diffuse reflectance spectra indicate that 1, 2, and 3 have potential applications in deep ultraviolet (DUV) regions.