The integration of catalyst metals into the graphene-based composites can be a new way to ensure thermal and electronic conductivities of the catalyst support materials in polymer electrolyte membrane fuel cells. In this work, graphene nanosheets were synthesized via a mild and safer chemical route including three major steps: graphite oxidation, ultrasonic treatment and chemical reduction. The...

Parameters and/or processes responsible for the stability of catalyst supports and ceramic membranes are discussed. Two major parameters/processes were identified which are responsible for the stabiliv of sol-gel derived nanostmctured oxides at elevated temperatures. They are metastable-to-stable phase transformation and structure and packing of primary particles within the aggregate. Based on ...

School of Chemistry, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa Email: ‡[email protected]; *[email protected] Carbon nanotubes (CNTs) possess unique properties which make them competitive with conventional catalyst supports. This short review collates fi ndings from many research groups on the benefi ts of palladium/carbon nanotubes in hydrogenat...

Structure, morphology and composition of two Pd/Ga2O3 methanol steam reforming catalysts were correlated with the associated activity and selectivity changes in the methanol steam reforming reaction and linked to studies on pure Ga2O3 supports. For both systems, that are, a Pd/Ga2O3 thin film model catalyst and a powder-supported Pd catalyst, we identified a temperature range in which the reduc...

in our current study, supercritical water impregnation (scwi) was introduced as a unique catalyst preparation method by employing the high diffusivity property of supercritical water. the method allows nano-particles to place on support surfaces in extremely dispersed conditions. the silica-based nanocatalyst granules for this purpose were prepared by initial impregnation of highly porous silic...

Direct alcohol fuel cells (DAFCs) are a type of electrochemical energy conversion device that directly Convert the chemical energy stored in a liquid alcohol fuel, commonly methanol and ethanol, and also ethylene glycol, or npropanol, to electricity. Because of their simplicity, high energy density, instantaneous recharging, and presumably long life, DAFCs have been identified as the most promi...

The hydroformylation of alkenes is a major commercial process used for the production of oxygenated organic compounds. When the hydroformylation reaction is performed using a homogeneous catalyst, an organic or aqueous solvent is employed, and a significant effort must be expended to recover the catalyst so it can be recycled. Development of a selective heterogeneous catalyst would allow simpli...

The effect of nanostructured supports on the activity of Rh catalysts was studied by comparing the catalytic performance of nanoand bulk-oxide supported Rh/ZnO, Rh/SiO2 and Rh/TiO2 systems in 1-hexene hydroformylation. The highest activity with 100% total conversion and 96% yield of aldehydes was obtained with the Rh/nano-ZnO catalyst. The Rh/nano-ZnO catalyst was found to be more stable and ac...

Ag-based catalysts with different supports (TiO2, Al2O3 and CeO2) were prepared by impregnation method and subsequently tested for the catalytic oxidation of formaldehyde (HCHO) at low temperature. The Ag/TiO2 catalyst showed the distinctive catalytic performance, achieving the complete HCHO conversion at around 95 °C. In contrast, the Ag/Al2O3 and Ag/CeO2 catalysts displayed much lower activit...