Gold-Nanotube Membranes for the Oxidation of CO at Gas-Water Interfaces

摘要

An exciting discovery in the area of heterogeneous catalysis is the observation that nanoparticles of gold on high-surface-area supports exhibit high activity for oxidation of CO with O_2 (CO + 1/2O_2 → CO_2) at room temperature. This discovery is of particular relevance for the production of fuel-cell-grade hydrogen, since carbon monoxide must be removed from hydrogen streams generated by catalytic reforming of hydrocarbons. The origins for the unique catalytic properties of supported gold catalysts are still unresolved. These properties have been related to changes in the electronic properties, the presence of defect sites, and the existence of strain for metallic gold nanoparticles. Unique catalytic properties have also been related to the presence of sites associated with the catalyst support, such as cationic gold species, and sites at gold-support interfaces.