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Two three-dimensional (3D) porous-layered borates, Na0.5K2.5[AlB7O13(OH)]·H2O (1) and NaKCs[GaB7O13(OH)]·1.5H2O (2), have been obtained under solvothermal conditions. Compound 1 crystallizes in the triclinic space group P1¯, while 2 crystallizes in the monoclinic space group P21/n. Compounds 1 and 2 contain similar units of B7O13(OH) and AlO4/GaO4; the strict alternations of B7O13(OH) clusters and AlO4/GaO4 resulted in 3D open-framework layers with 8-R and 13-R channels along different directions. The shapes and orientations of the channels of 1 and 2 are different due to their different space groups. It's interesting to note that three different alkali metal ions (Na+, K+, and Cs+) are found in different positions in 2. UV-vis diffuse reflectance analysis indicates that both compounds show a wide transparency range with a short-wavelength absorption edge below 190 nm. [ABSTRACT FROM AUTHOR]

The search for laser-ignitable energetic materials catering to the safety and accuracy requirements in military and civilian affairs is an important yet challenging task. In this work, non-explosive and stable nitro bearing ligands of 3,5-dinitro-4-chlorobenzoic acid (HDNB-Cl) and 3,5-dinitro-4-hydroxybenzoic acid (HDNB-OH) have been adopted as energetic modules and organic building units to assemble with copper ions to construct energetic coordination complexes. The d–d transition introduced by Cu2+ endows the as-synthesized compounds to display remarkable absorptions of NIR light, and thus achieve efficient photothermal conversions upon irradiation by an 808 nm laser. As a result, the DNB-Cl based complexes can be laser-ignited and strong deflagration has been observed. The satisfactory thermal stability and tolerance toward friction and electrostatic discharge make them good candidates as laser-ignitable energetic materials. Unlike the conventional energetic materials based on nitrogen-rich organics (e.g., azido, furazan, and heterocyclic compounds), this work reveals that the easily functionalized nitro-bearing carboxylate ligand is an alternative energy module for assembling stable energetic complexes, and the coordination interaction-induced photothermal conversion would be an efficient strategy to achieve laser ignition for the resultant energetic compounds. [ABSTRACT FROM AUTHOR]

Using the photosensitized Ru(N∧N∧N)2-metalloligand, a series of Ce frameworks were synthesized. The incorporation of the visible-light-responsive Ru(N∧N∧N)2-unit endows the Ce frameworks with photocatalytic activities in both sulfide oxidation and hydrogen production. The doping of Zr and particularly the oxidation state of Ce has great influence on the photocatalytic properties of the Ce frameworks. [ABSTRACT FROM AUTHOR]

Two new B3O7 cluster-based borates, [B6O9(OH)2]·H2dap (1, dap = 1,2-diaminopropane) and Li0.5Ca0.5[B3O5][BO(OH)2]0.5 (2), were solvothermally synthesized using different organic and inorganic templates, respectively. In 1, two different B3O7 clusters interconnect to construct a rare 2D fluctuant layer with 11-MR unclosed channels. Templating [H21,2dap]2+ located in the interlayers stabilizes the layers through H-bonds. 2 features an acentric 3D open framework with 17-MR large channels built by 4-connected B3O7 clusters. Guest Li-BO(OH)2-Ca 1D chains intercalate in the 17-MR channels, directing the formation of the 3D open framework through host–guest symmetry and charge matching. 2 is a phase-matchable nonlinear optical (NLO) material with a second-harmonic generation (SHG) response ∼1.6 times that of KDP (KH2PO4). UV-vis absorption spectra reveal that 1 and 2 have short cut-off edges of 205 and 213 nm, respectively, indicating that 1 is a wide-band semiconductor and 2 is a UV NLO material. [ABSTRACT FROM AUTHOR]

Three new mixed-alkaline-metal borates, namely KNa8[Li@B12O18(OH)6](CO3)2 (1), Cs10[Li@B12O20(OH)2]2·6H2O (2) and Cs5[Li@B12O20(OH)2]·3H2O (3), have been synthesized under hydro/solvothermal conditions. Compound 1 is a borate carbonate with the isolated [Li@B12O18(OH)6]5− clusters and interesting layers formed by Na+ and CO32− ions, forming a 2D supramolecular structure with a 3,6-connecting binodal system. After changing the synthetic conditions, the isolated [Li@B12O18(OH)6]5− clusters are successfully extended to the layers in 2 and 3 by condensation reactions with the elimination of water molecules between oxoboron clusters. Each new fundamental building block [Li@B12O22(OH)2]9− in 2 and 3 connects with four neighboring units to form a 2D layer via B–O–B bonds for the first time, and 14-membered rings are also observed. Such a layer structure is first observed in dodecaborates. Since compound 3 crystallizes in the non-centrosymmetric space group, the second harmonic generation measurement and the dipole moments calculation have been carried out. [ABSTRACT FROM AUTHOR]

Three new metal borates, namely K0.5[B6O10]·H2O·1.5H3O (1), [GaB5O10]·H2en (2) and NaCs[Ga{B5O9(OH)}{BO(OH)2}] (3), have been synthesized under solvothermal conditions. Compound 1 features an intricate 3D framework composed of [B6O13]8− clusters, resulting in a 6-connected achiral pcu net. After introducing the organic gallium, one of the BO4 groups of the [B6O13]8− cluster is substituted by a GaO4 polyhedron to form the acentric [GaB5O13]8− cluster in 2. It also displays a high second-harmonic generation (SHG) response about approximately 2.6 times that of KH2PO4 (KDP), which is higher than those of alumino-borates (ABOs) containing the acentric [AlB5O13]8− cluster (0.3–2.1 times that of KDP). Dipole moment calculations have been carried out to confirm these results. In the process of trying to synthesize a new compound with a denser structure than 2, we have unexpectedly obtained 3 crystallized in the centrosymmetric (CS) space group, which shows a 1D structure constructed from the [Ga{B5O9(OH)}{BO(OH)2}]2− cluster. This kind of low-dimensional structure is rare in gallo-borates (GBOs) as well as ABOs. [ABSTRACT FROM AUTHOR]

Three new hexa-NiII-substituted organic–inorganic hybrid polyoxotungstates, H[Ni0.5(en)(H2O)][Ni6(en)3(OAc)2(Tris)(H2O)2(B-α-PW9O34)]·5H2O (1), [Ni(en)2][Ni6(en)3(μ3-OH)3(1,3-bdc)(H2O)2(B-α-PW9O34)]·9H2O (2) and [Ni(en)(H2O)4]3[Ni6(en)3(Tris)(1,3-bdc)1.5(B-α-PW9O34)]2·8H2O (3) (en = ethylenediamine, Tris = tris(hydroxymethyl)aminomethane, 1,3-bdc = 1,3-benzenedicarboxylate) were hydrothermally synthesized and characterized. Both 1 and 3 contained {Ni6(Tris)(en)3(B-α-PW9O34)} units, whereas 2 was constructed from [Ni6(en)3(μ3-OH)3(B-α-PW9O34)] units. 1 is a new monomer. 2 comprises a 1-D chain built by [Ni6(en)3(μ3-OH)3(B-α-PW9O34)] structural building units (SBUs) linked by 1,3-bdc ligands. 3 represents the first 2-D polyoxometalate cluster-organic frameworks (PCOFs) with a honeycomb-like lattice that consists of [Ni6(en)3(Tris)(B-α-PW9O34)] SBUs linked by 1,3-bdc ligands. 1 indicated ferromagnetic coupling interactions existing in the hexa-NiII clusters. 1–3 showed excellent adsorption capabilities for MB and 3 exhibited good electrocatalytic activities for H2O2 and NaNO2 reduction. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of H3BO3, Li2B4O7, Na2B4O7·10H2O, 1,2-diaminopropane and pyridine led to a new open framework borate, Li2Na2[B12O19(OH)2] (1). Compound 1 crystallizes in the monoclinic space group C2/c. Its structure contains a large cyclic [B12O22(OH)2]10− cluster, which is connected to six neighboring ones via corner-sharing O atoms to give a 6-connected pcu network via B–O–B bonds. Notably, large shuttle-like pores are observed along the [001] direction as well as 8-ring channels along the [101] direction, leading to an intersecting channel system. UV/vis diffuse reflectance analysis indicates that the compound has a wide transparency range with a short-wavelength absorption edge below 200 nm. [ABSTRACT FROM AUTHOR]

In this article, two new tetra-Zr(iv)-substituted sandwich-type Keggin polyoxometalates functionalized by chiral d-tartaric acid and glycolic acid, K2H10[Zr4(H2O)2(μ-OH)(μ3-O)2(d-tartH)(GeW10O37)2]·27H2O (1, D-tartH4 = d-tartaric acid) and K2H10[Zr4(H2O)2(μ3-O)2(gly)2(GeW10O37)2]·32H2O (2, glyH2 = glycolic acid), have been synthesized under hydrothermal conditions and characterized by FT-IR spectra, elemental analysis, single-crystal X-ray structure analysis, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), ultraviolet-visible absorption spectroscopy (UV-vis) and cyclic voltammetry (CV). The structure analysis reveals that both 1 and 2 contain a [Zr4(H2O)2(μ3-O)2(GeW10O37)2] cluster. UV-vis spectra indicate that both compounds are a wide-gap semiconductor. In addition, compound 1 is a chiral Zr(iv)-substituted sandwich-type Keggin cluster because the d-tartH ligand is chiral and the Flack divisor of 1 is 0.00, showing non-linear optical properties. The cyclic voltammograms indicate that compounds 1 and 2 have good electrocatalytic activity in the reduction of H2O2. [ABSTRACT FROM AUTHOR]