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Two unique 22-core sandwich {[Mn 6 Mo 6 O 37 ]Ln 3 [MnMo 6 O 24 ]} (Ln = La or Pr) units have been assembled, featuring an undisclosed {Mn 6 Mo 6 } cluster. This assembly is subsequently integrated into two three-dimensional polyoxometalate organic frameworks, which exhibit one-dimensional hydrophilic hexagonal channels formed by six intertwined 6 3 helical chains, leading to effective proton conduction primarily facilitated by an abundance of water molecules within the channels.

Lanthanide-containing polyoxometalate-based metal-organic frameworks (POMOFs) not only enjoy intriguing architectures but also have good application prospects as catalysts. Herein, three novel three-dimensional (3D) POMOFs with the formulas of {H[Ln 3 (2,6-pydc) 2 (H 2 O) 10 (MnMo 9 O 32 )]·2H 2 O} n (Ln = La( 1 ), Pr( 2 ), Nd( 3 )) have been synthesized based on Waugh-type [MnMo 9 O 32 ] 6- anions and pyridine-2,6-dicarboxylate (2,6-H 2 pydc). Compounds 1 - 3 are isomorphic, and there are two kinds of one-dimensional (1D) helical chains with opposite handedness staggered into two-dimensional (2D) layers. Interestingly, the coordinated L - and R -[MnMo 9 O 32 ] 6- anions are encapsulated in 1D chains with the same chirality and are further expanded into 3D structures. The catalytic tests indicate that compounds 1 - 3 exhibit high-efficiency heterogeneous catalytic activity in the oxidative desulfurization reaction for catalyzing the oxidation of sulfides to sulfoxides using tert -butyl hydrogen peroxide (TBHP) as the oxidant. Moreover, a series of control experiments have been conducted to investigate the influence of various parameters such as temperature, time, solvent, catalyst, and substrate on the reaction. Significantly, compound 2 , as an example, exhibits good reusability and structural stability in the oxidative desulfurization reaction. It is worth noting that investigations on the oxidative desulfurization of [MnMo 9 O 32 ] 6- anions are scarce. Moreover, their electrochemical properties are also explored.

Achieving long-term stable deep desulfurization at room temperature and recovering high value-added sulfone products is a challenge at present. Herein, a series of catalysts [C n mim] 5 VW 12 O 40 Br (C n VW 12 , 1-alkyl-3-methylimidazolium bromide tungstovanadate, n = 4, 8, 16) were presented for the room temperature catalytic oxidation of dibenzothiophene (DBT) and its derivatives. Factors affecting the reaction process, such as the amount of catalyst, oxidant, and temperature, were systematically discussed. C 16 VW 12 showed higher catalytic performance, and 100% conversion and selectivity could be achieved in 50 min with only 10 mg. The mechanism study showed that the hydroxyl radical was the active radical in the reaction. Benefiting from the "polarity strategy", the sulfone product accumulated after 23 cycles in a C 16 VW 12 system, and the yield and purity were about 84% and 100%, respectively.

Four novel three-dimensional interpenetrating frameworks based on {P 4 Mo 6 } units, H[C 12 H 14 N 2 ] 4 [TM 4 (PO 4 )(H 2 O) 4 Na 6 ][TM 2 (Mo 6 O 12 (HPO 4 ) 3 (PO 4 )(OH) 3 ) 4 ]·8H 2 O ( 1 , 2 ) and H[C 14 H 18 N 2 ] 4 [TM 4 (PO 4 )(H 2 O) 4 Na 6 ][TM 2 (Mo 6 O 12 (HPO 4 ) 3 (PO 4 )(OH) 3 ) 4 ]·8H 2 O ( 3 , 4 ) (TM = Co 2+ ( 1 , 3 ), Mn 2+ ( 2 , 4 )) were synthesized and characterized using infrared spectroscopy, elemental analyses, thermogravimetric analysis, and single-crystal X-ray diffraction. In situ generated methyl viologen (compounds 1 and 2 ) or ethyl viologen (compounds 3 and 4 ) cations function as templates to induce the generation of 2-fold interpenetrating structures in which the {P 4 Mo 6 } tetrameric clusters with [TM 4 (PO 4 )Na 6 ] (TM = Co 2+ ( 1 , 3 ) and Mn 2+ ( 2 , 4 )) as the core were bridged by transition metal ions. Compounds 1 - 4 possess high thermal stabilities and the decomposition temperature of the inorganic frameworks were all >500 °C. It is worth noting that the four compounds all exhibited the bifunctional catalytic performance that they not only had an excellent photocatalytic activity for the reduction of hexavalent chromium (Cr(VI)) under visible light irradiation but also showed a good electrocatalytic activity for the reduction reaction of hydrogen peroxide.

The largest antimonomolybdate monomer, [Sb 8 Mo VI 13 Mo V 5 O 66 ] 5- ( 1- Sb 8 Mo 18 ), has been isolated and displays a new breakthrough of polyoxometalates (POMs) with an ionothermal synthesis strategy. 1-Sb 8 Mo 18 features the first hexanuclear sandwich-type polymolybdate (POMo) with an unexpected metal ring {Sb 6 O 12 } to make its debut in Sb clusters. Furthermore, 1-Sb 8 Mo 18 exhibits a prominent catalytic activity for reducing nitrobenzene to aniline with excellent sustainability.

Five novel interesting d(10) metal coordination polymers, [Zn(PDCO)(H2O)2]n (PDCO = pyridine-2,6-dicarboxylic acid N-oxide) (1), [Zn2(PDCO)2(4,4'-bpy)2(H2O)2.3H2O]n (bpy = bipyridine) (2), [Zn(PDCO)(bix)]n (bix = 1,4-bis(imidazol-1-ylmethyl)benzene) (3), [Zn(PDCO)(bbi).0.5H2O]n (bbi = 1,1'-(1,4-butanediyl)bis(imidazole)) (4), and [Cd(PDCO)(bix)(1.5).1.5H2O]n (5), have been synthesized under hydrothermal conditions and structurally characterized. Polymer 1 possesses a one-dimensional (1D) helical chainlike structure with 4(1) helices running along the c-axis with a pitch of 10.090 Angstroms. Polymer 2 has an infinite chiral two-dimensional (2D) brick-wall-like layer structure in the ac plane built from achiral components, while both 3 and 4 exhibit an infinite 2D herringbone architecture, respectively extended in the ac and ab plane. Polymer 5 features a most remarkable and unique three-dimensional (3D) porous framework with 2-fold interpenetration related by symmetry, which contains channels in the b and c directions, both distributed in a rectangular grid fashion. Compounds 1-5, with systematic variation in dimensionality from 1D to 2D to 3D, are the first examples of d(10) metal coordination polymers into which pyridinedicarboxylic acid N-oxide has been introduced. In addition, polymers 1, 4, and 5 display strong blue fluorescent emissions in the solid state. Polymer 3 exhibits a strong SHG response, estimated to be approximately 0.9 times that of urea.

A nonplanar metallacrown [Ni-N-N]12 was achieved using a pentadente ligand, salicylaldehyde 2-pyridinecarboxylhydrazone (H2L) via a new modular self-assembly approach. The special bridging models of the ligand forced the macrocycle to form in a specific size with the wavelike conformation.