Supported nano-alloys have been prepared using the sol-immobilisation method for two bimetallic combinations, namely gold-platinum and palladium-platinum, using activated carbon and titania as supports. Some of the materials were prepared using a method where both metals are simultaneously reduced, thereby leading to homogeneous alloys being formed. In addition, sequential reduction of the metal combinations has also been investigated to facilitate the formation of core-shell structures. The materials have been characterized using X-ray photoelectron spectroscopy and aberration-corrected scanning transmission electron microscopy. The supported nanoparticles have been tested for a two selective oxidation reactions, namely the oxidation of toluene and benzyl alcohol using tertiary butyl hydroperoxide at 80 °C, in order to elucidate any potential structure-activity relationships.

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Partial oxidative upgrading of C -C alkanes over Cu/ZSM-5 catalysts prepared by chemical vapour impregnation (CVI) has been studied. The undoped ZSM-5 support is itself able to catalyse selective oxidations, for example, methane to methanol, using mild reaction conditions and the green oxidant H O . Addition of Cu suppresses secondary oxidation reactions, affording methanol selectivities of up to 97 %. Characterisation studies attribute this ability to population of specific Cu sites below the level of total exchange (Cu/Al<0.5). These species also show activity for radical-based methane oxidation, with productivities exceeding those of the parent zeolite supports. When tested for ethane and propane oxidation reactions, comparable trends are observed.

We report the oxidation of propane under mild aqueous conditions using H2O2 as the oxidant.

Fe‐containing ZSM‐5 catalysts are reported to be efficient catalysts for the partial oxidation of propane to oxygenated products at reaction temperatures as low as 50 °C in an aqueous phase reaction when using the green oxidant H2O2. It was previously proposed that extra framework Fe species at the exchange sites of the zeolite are responsible for activation of both the alkane and hydrogen peroxide. Through a systematic study of the influence of framework topology and exchange properties, it is now shown that this high catalytic activity is specific to the MFI‐type Brønsted acidic zeolite ZSM‐5. Furthermore, through a simple aqueous acid washing treatment, leaching of approximately 77 % of iron present within a Fe/ZSM‐5 catalyst only caused the relative propane conversion to decrease by 17 %; implying that most of the initially loaded Fe does not actually contribute to the catalytic activity. This small change in conversion after ‘excess’ Fe removal, amounts to a three‐fold increase in turnover frequency (TOF) (Fe) from 66 h−1 to 232 h−1 compared with the parent Fe/ZSM‐5 catalyst. By comparing these samples, it is shown by NH3 temperature‐programmed desorption, 27Al magic angle spinning NMR spectroscopy, X‐ray photoelectron spectroscopy and TEM analysis that surface iron oxide species are effectively spectators in the oxidation of propane with H2O2. This provides further insight as to the location and true nature of the catalytically active Fe species.