Syntheses and structures of a new 2D layered borate and a novel 3D porous-layered aluminoborate.

Two new layered and porous-layered borates ([Hdap][BO(OH)] (1, dap = 1,2-propanediamine) and [HO]KNa{Al[BO(OH)][BO][BO]}[CO] (2)) have been solvothermally made. 1 features a 2D layer made of the [BO(OH)] cluster, in which Hdap is located in the windows of the layers. The fundamental building block (FBB) [BO(OH)] cluster in 1 represents a new type of FBB of the hepta-borate family. 2 is a novel aluminoborate with a 3D porous-layered structure formed by three types of oxoboron clusters, [BO(OH)], [BO] and [BO], respectively. The strict alternation of the different oxoboron clusters and AlO tetrahedra leads to the abundant channel systems of the structure. 2 is the first aluminoborate (ABO) containing three types of oxoboron clusters and the first 3D porous-layered ABO with seven types of channels. UV-vis diffuse reflectance spectra reveal that both of them are wide band-gap semiconductors and have potential applications in UV regions.