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Abstract: Series of Rh/SBA-15 catalysts were prepared by impregnation and grafting method applying different Rh precursors. The catalytic behaviors of N2O decomposition over these catalysts were tested in an automated eight flow reactor system. The catalysts were characterized by X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), N2 adsorption/desorption, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. The results showed that the dispersion of Rh species on the catalysts is closely related to the molecular size and the hydrophobic property of the precursors comparing to the hydrophilic support, better dispersion results were found in catalysts by impregnation of smaller precursors, while by grafting better dispersion resulted from big precursor. On the other hand, the activities of the catalysts match well with the Rh dispersion status. Rh/SBA-15-CDCR starting from [(CO)2RhCl]2 showed good dispersion and gave the best N2O decomposition activity. [Copyright &y& Elsevier]

The acidity and Ga-species status in the zeolite play a crucial role in the CO 2 -assisted propane dehydroaromatization (CO 2 -PDA). In this work, a copper modified Ga-MFI zeolite (Cu/Ga-MFI) with well dispersed framework Ga species was fabricated. A remarkable aromatics selectivity of 73% at propane conversion of 93.6% was achieved on Cu/Ga-MFI catalyst. The Ga atoms in MFI framework can create a moderate acid strength, while the introduced Cu provide an appropriate Brønsted/Lewis acid distribution, enhancing the synergy between metal-related species and the zeolite. Besides, DFT results indicate that the acid sites in Ga-MFI are more preferable for the dehydrogenation of propane instead of the C-C cleavage. Moreover, CO 2 can inhibit coke formation through reverse Boudouard and reverse water gas shift reaction, which endows Cu/Ga-MFI catalyst with superior anti-coking ability and regeneration stability. This work provides a novel approach for designing catalysts with high activity, aromatics selectivity, and stability for CO 2 -PDA reactions. [Display omitted] • H-type Al-free Ga-MFI with Ga located in frameworks is successfully fabricated. • Cu/Ga-MFI shows a superior aromatics selectivity and stability in CO 2 -PDA reaction. • The moderate acid strength from Ga in MFI is favored by propane dehydrogenation. • The synergy between Brønsted/Lewis acid is crucial for catalytic performance. • The introduction of Cu promotes CO 2 activation and inhibits the carbon deposition. [ABSTRACT FROM AUTHOR]

Constructing non-noble robust catalysts for deep catalytic oxidation of obstinate light alkanes at low temperature is of great value and significance. Herein, we designed a facile solvent-thermal-reduction strategy to fabricate an O-vacancy-rich porous MnO 2 nanosheet (MnO 2 −PS) catalyst for propane catalytic oxidation. The abundant vacancies in MnO 2 −PS catalysts can significantly promote its redox ability and oxygen activation capacity, and then provide more active oxygen species with enhanced oxygen mobility and reactivity, thus accelerate the cleavage of C-H bond and the decomposition of intermediates. Meanwhile, benefiting from the porous nanosheet structure, MnO 2 −PS catalyst possesses highly accessible surface and high density of exposed active sites, thus facilitating the adsorption and the activation of reactant molecule. At the same time, the catalyst also exhibits good thermal stability and water resistant ability. This robust and efficient catalytic system may provide some enlightenments for designing feasible catalyst with high-performance for deep catalytic destruction of VOCs. [Display omitted] • O-vacancy-rich porous MnO 2 nanosheets (MnO 2 –PS) catalyst were fabricated through a facile method. • High catalytic performance of propane catalytic oxidation on MnO 2 –PS catalyst was achieved. • The MnO 2 –PS with abundant vacancies exhibits higher density of exposed active sites, higher redox ability and oxygen mobility. [ABSTRACT FROM AUTHOR]