The maximum exposure of polyoxometalates (POMs) is of great significance to enhance the catalytic performance of HKUST-1 with incorporated Keggin-type POMs. Herein, two phosphovanadomolybdates were encapsulated into the HKUST-1 via a hydrothermal method to obtain two polyoxometalate-based metal–organic frameworks, formulated as [Cu12(BTC)8(H2O)12]­[H4PMo11VO40]@(H2O)30 (1) and [Cu12(BTC)8(H2O)12]­[H5PMo10V2O40]@(H2O)49 (2). Single-crystal X-ray diffraction analysis indicates that two compounds contain unique high-nuclearity water clusters without organic counter cations. The octahedral-shaped water cluster (H2O)30 was constructed from square-pyramid-shaped (H2O)5 for compound 1, while the huge cage-shaped water cluster (H2O)49 of compound 2 consisted of crown-like (H2O)8 and one water molecule, which substitute the organic counter cations involved in the structural construction. More importantly, after removing the water clusters via simple heat treatment, the active sites of the two compounds were fully exposed, leading to good catalytic activities for both benzene hydroxylation reaction and oxidative desulfurization. Furthermore, the catalytic test confirmed that compound 2 may be a bifunctional heterogeneous catalyst with great promise for both benzene hydroxylation and oxidative desulfurization.

A series of novel 3D 3d-4f heterometallic cluster-based coordination polymers, [Ln4Cr4(μ3-O)4(μ4-O)4(NA)8(H2O)12]·xH2O (Ln = 1-Gd, 2-Tb, 3-Er; HNA = nicotinic acid; x = 13 (1-Gd), 11.33 (2-Tb), 15 (3-Er)), have been successfully synthesized by hydrothermal method using nicotinic acid as bridging ligand. The single-crystal X-ray diffraction (SCXRD) analysis indicated that the basic unit of Ln4Cr4 shows a butterfly-shaped structure. Furthermore, each Ln4Cr4 cluster connects with other four Ln4Cr4 clusters by bridging NA– ligands to form a 3D structure containing interesting 1D honeycomb-shaped coordination nanotubes. The variable temperature magnetic susceptibility measurements of compound 1 revealed that the existence of antiferromagnetic (AF) coupling between the metal ions in the Gd4Cr4 clusters. Field-dependent isothermal magnetization studies displayed that the magnetic entropy change (−ΔS m) value of 1-Gd reached 22.05 J K–1 kg–1.

Photocatalytic CO2 reduction (CO2RR) into high-value products is of great significance not only in addressing global warming but developing sustainable energy. Herein, two novel metal organic frameworks (MOFs) induced by...

Two heterometallic cluster {Ln8Cr4} were constructed from two classical “drum-like” {Ln4Cr2} building units associated by organic ligands HIN, displaying 1D wave chain structure. The MCE values for {Gd8Cr4} at 3 K and 7 T is 23.40 J kg−1 K−1.

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