ABSTRACT
Three new aluminoborates (ABOs) KCs[Al{B5O9(OH)}{BO(OH)2} (1), K0.5Cs[Al{B5O10}1/2{BO2(OH)}] (2), and Cs1.5[Al{B5O10}1/2{BO2(OH)}] (3) have been made under solvothermal conditions. 1 features a 1D tube constructed by the alternation of [B5O9(OH)]4- clusters and AlO4 units, onto which the [BO(OH)2]- 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 [B5O10]5- clusters, AlO4 tetrahedra and [BO2(OH)]2- triangles, in which [B5O10]5- clusters are bridged by AlO4 tetrahedra to produce a 2D ABO layer with 14-membered ring (MR) windows, and the [BO2(OH)]2- 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.
ABSTRACT
A novel 40Ni-added germanotungstate, Cs8K14Na3H3{[Ni6(OH)3(H2O)6(B-α-GeW9O34)]2[Ni8(µ6-O)(µ2-OH)2 (µ3-OH)2(H2O)B2O3(OH)2(B-α-GeW9O34)2]}2·84H2O (1), was made by the reaction of the trivacant [A-α-GeW9O34]10- ({GeW9}) precursor with Ni2+ cations and B5O8-, and systematically investigated by Fourier-transform infrared spectroscopy, elemental analysis, thermogravimetric analysis, and powder X-ray diffraction. Single crystal X-ray analysis indicates that the polyoxoanion of 1 is a novel octamer constructed by {Ni6GeW9} and {Ni8(GeW9)2} structural building units via Ni-OâW linkages. The magnetic behavior shows the existence of overall ferromagnetic interactions among the Ni2+ centers in compound 1. Photocatalytic H2 production studies have implied that 1 can work as a heterogeneous catalyst for hydrogen production with decent robustness and recyclability.
ABSTRACT
Driven by the synergistic-directing effect of the lacunary fragments, [B-α-GeW9O34]10- and [B-α-GeW11O39]8-, an unprecedented hepta-Zr-substituted polyoxometalate (POM) assembly K2Na6H10(Hpy)3[SbZr7O6(OH)4(B-α-GeW9O34)2(B-α-GeW11O39)2]·28H2O (1) was made under hydrothermal condition and structurally characterized. Of which, a unique hepta-Zr cluster, [SbZr7O6(OH)4]15+ core, was built by two trilacunary [B-α-GeW9O34]10- fragments and two monolacunary [B-α-GeW11O39]8- fragments and further arranged in a mode of a vertical cross and formed a pseudo-tetrahedron geometry. Compound 1 features the first Zr7-cluster-substituted POM. Moreover, 1 is an effective heterogeneous catalyst for the catalytic oxidation of sulfides into the corresponding sulfones with H2O2, manifesting distinguished conversion, excellent yield, and desired recyclability.
