A novel method has been developed for preparing supported cubic platinum nanoparticles. Carbon monoxide and hydrogen are used to reduce platinum precursors present at a solid-gas interface and to control the shape of the growing Pt nanoparticles. By avoiding the use of any organic agents in the synthesis, cubic Pt particles free of hydrocarbons are formed, thereby avoiding possible contaminatio...

Traditional analysis of reactions catalyzed by supported metals involves the structure of the metallic particles. However, we report here that for the class of nanostructured gold- or platinum-cerium oxide catalysts, which are active for the water-gas shift reaction, metal nanoparticles do not participate in the reaction. Nonmetallic gold or platinum species strongly associated with surface cer...

BACKGROUND South Africa is the largest producer of platinum group metals in the world. Platinum is found in the Bushveld Complex in the north-east of the country. This volcanic intrusion contains many other minerals, including crystalline silica. Little is known about the health risks in the platinum mining industry. AIMS To explore the potential for platinum mine workers to develop silicosis...

In this contribution, we report the successful preparation of supported metal catalysts using dendrimer-encapsulated Pt nanoparticles as metal precursors. Polyamidoamine (PAMAM) dendrimers were first used to template and stabilize Pt nanoparticles prepared in solution. These dendrimer-encapsulated nanoparticles were then deposited onto a commercial high surface area silica support and thermally...

In Pt/ZrO2 catalysts used for CO2/CH4 reforming to syngas, not all accessible Pt contributes equally to the activity of the catalyst. The catalytic activity is determined by the accessibility of Pt on the Pt-ZrO2 perimeter. This is explained in terms of the CO2 activation via carbonate species on the support which must be in the proximity of the Pt particles to react with the methane activated ...

Various platinum-free electrocatalysts have been explored for hydrogen evolution reaction in acidic solutions. However, in economical water-alkali electrolysers, sluggish water dissociation kinetics (Volmer step) on platinum-free electrocatalysts results in poor hydrogen-production activities. Here we report a MoNi4 electrocatalyst supported by MoO2 cuboids on nickel foam (MoNi4/MoO2@Ni), which...