The Keggin-type polyoxometalates (POMs) are effective catalysts for oxidative desulfurization (ODS) and confining these POMs in metal-organic frameworks (MOFs) is a promising strategy to improve their performances. Herein, postsynthetic modification of POMs confined in MOFs by adding thiourea creates more unsaturated metal sites as defects, promoting ODS catalytic activity. Additional modification by confining 1-butyl-3-methyl imidazolium POMs in MOFs is performed to obtain higher ODS activity, owing to the affinity between electron-rich thiophene-based compounds and electrophilic imidazolium compounds. The ODS catalytic activities of fourZr-MOF-based composites (bottle around ship) including phosphomolybdate acid (PMA)/UiO-66, [Bmim] 3 PMo 12 O 40 /UiO-66, PMA/Thiourea/UiO-66, and [Bmim] 3 PMo 12 O 40 /Thiourea/UiO-66 are therefore investigated in detail.In order to explore the catalytic mechanism of these MOF composites, their microstructures and electronic structures are probed by various techniques such as X-ray diffraction, thermogravimetric analysis, Fourier transform infrared, Raman, scanning electron microscope, transmission electron microscope, BET, X-ray photoelectron spectroscopy, EPR, UV-vis, NMR spectra, and H 2 -temperature-programmed reduction. The results reveal that phosphomolybdate blues and imidazolium phosphomolybdate blues with different Mo 5+ /Mo 6+ ratios with the Keggin structure are confined in defected UiO-66 for all four composites. This approach can be applied to design and synthesize other POMs/MOFs composites as efficient catalysts.

A highly hydrophobic Cu(ii) MOF (UPC-21) was synthesized through a newly developed “diauxic growth” strategy. The multi-aromatic hydrocarbon units in the framework are responsible for hydrophobic character of UPC-21. Its application on water purification and oil/water separation was studied for the first time.

Dehydration and catalytic cracking reactions can be combined to convert glycerol into light olefins using solid acid catalysts. The combination is suitable for a singlestep process to convert glycerol into light olefins at high temperatures (26−36% selectivity at 873 K). However, large quantities of carbon oxides are produced (31−39% CO x selectivity), and catalyst deactivation also occurs. High light olefin selectivity (62−65%) and a smaller quantity of carbon oxides (11−12% CO x selectivity) can be obtained by using a tandem process involving the dehydration of glycerol and subsequent catalytic cracking of the dehydration products (mainly acetol and acrolein). Furthermore, the ratio of propylene to ethylene can be adjusted by changing the dehydration catalysts to favor the production of acetol or acrolein: Acetol forms propylene, and acrolein forms ethylene. To overcome the fast deactivation of acid catalysts in glycerol dehydration, the hydrogenolysis and catalytic cracking reactions can be synchronized to convert glycerol into hydrocarbons using a combination of metal and acid catalysts. The single-step conversion of glycerol over a metal or bifunctional catalyst formed alcohols and paraffin. The highest selectivity for propylene production (approximately 76%) was obtained in a tandem process via the selective hydrogenolysis of glycerol to propanols over Pt/ZSM-5 catalysts followed by the catalytic dehydration/cracking of propanols to propylene over ZSM-5 catalysts at low temperatures (523 K). The selectivity for propylene was improved by increasing the Si/Al ratio of the ZSM-5 catalysts and the reaction time. Under these conditions, economically competitive crude glycerol (mainly mixtures of glycerol and methanol) can be used to synthesize light olefins (approximately 61% selectivity) with a long lifetime (∼500 h) in single-route reactions by increasing the cracking temperature to 773 K, which is suitable for practical methanol to propylene process.

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1.439 V of open-circuit voltage and 1413.3 Wh•kg −1 of energy density.

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An amorphous Ni-B/TiO 2 catalyst has been synthesized by silver-catalyzed electroless nickel plating. The amorphous structure of Ni-B nanoparticles was characterized by X-ray diffraction (XRD) and selected area electron diffraction (SAED). A transmission electron micrograph (TEM) of the Ni-B/TiO 2 showed particles with size ranging from 30 to 50 nm were homogeneously dispersed over TiO 2 support. High-resolution transmission electron microscopy (HRTEM) indicated that the Ni-B nanoparticles presented a porous and flower-like morphology, which was different from the solid sphere of conventional Ni-B particles prepared by impregnation-reduction method. To investigate the formation process of the porous Ni-B particles, the diffusion of nickel nuclei and the growth of Ni-B particles were characterized. The as-prepared porous Ni-B/TiO 2 catalyst exhibited superior catalytic activities in the hydrogenation reactions to those of catalysts prepared by conventional methods.