Structural and chemical stability of the immobilized polyoxometalates (POMs)-containing catalysts is one crucial factor for their industrial application. In this work, we discuss the preparation of a novel P2W15@Al2O3 catalyst using a facile condensation reaction between the tri-lacunary POM of Na12[α-P2W15O56]·24H2O (P2W15) and the hydroxyl groups on the surface of the spherical γ-Al2O3 under acidic conditions. The heterogeneous catalyst was characterized by the 31 P NMR, FT-IR, XRD, XPS, TG, Raman, HR-TEM and BET. The P2W15@Al2O3 catalyst showed excellent stability, highly efficient reactivity and selectivity for the oxygenation of thioethers to sulfoxides which are a very useful intermediate in organic synthesis and industrial preparation of drugs. The catalyst could be recycled and reused at least ten times without any observable loss of its catalytic efficiency, mainly due to the covalently grafted {P2W15} cluster and high dispersion onto the γ-Al2O3 surface.Polyoxometalates (POMs) are a class of discrete anionic metal-oxides of V, Mo, W and Nb etc.

Deep desulfurization of fuels has long been and remains to be a highly challenging issue. In this work, a trilacunary polyoxometalate of Na12[α-P2W15O56]·24H2O (P2W15) was covalently tethered onto the γ-Al2O3 sphere, to which different alkyl chains (C n , n = 8, 12, or 18) were grafted, leading to the formation of the Al2O3-P2W15-C n . When the Al2O3-P2W15-C n were applied to catalyze oxidative desulfurization reaction of dibenzothiophene (DBT) in the presence of H2O2, it displayed high efficiency for removal of sulfur content in 9 min under optimized conditions at 60 °C. In addition, the Al2O3-P2W15-C n exhibited excellent structural stability during the catalytic reaction and can be used to remove 4,6-dimethyldibenzothiophene (4,6-DMDBT) and benzothiophene (BT) from fuel oils. The excellent performance of Al2O3-P2W15-C18 was verified by sulfur removal for an actual diesel sample. Molecular dynamics simulations indicated that DBT showed strong tendency to be adsorbed on active sites, while DBTO2 (dibenzothiophene sulfone) can be desorbed much easier. This work opens up a new avenue for further study on oxidative desulfurization catalytic materials and the influence of catalyst structure on mass transfer.

The structural and chemical stability of immobilized polyoxometalate (POM)‐containing catalysts are crucial for their industrial application. A highly stable catalyst was prepared by linking [α‐P2W15O56]12− clusters with a spherical γ‐Al2O3 support. In the cover image, the [α‐P2W15O56]12− clusters are depicted as a functional device immobilized on a basal chip (representing the γ‐Al2O3 support). As a result, different signals can get through the functional devices and be processed to give a signal (the product). Such multifunctional catalysts can be designed on a smart chip to catalyze multistep reactions in the near future. More information can be found in the Full Paper by W. Chen, Y.‐F. Song et al. on page 11232 ff.