Abstract: The invention relates to a gold-containing catalyst with porous structure that is obtainable through a process that comprises the following steps: melting together of gold and at least one less noble metal that is selected from the group consisting of silver, copper, rhodium, palladium, and platinum, and at least partial removal by dissolving the at least one less noble metal out of the starting alloy thus obtained. The catalyst has high activity and great long-term stability, despite the fact that it does not contain a support material or a compound that serves as a support material. The catalyst can be used to accelerate and/or to influence the product selectivity of oxidation and reduction reactions. The catalyst is suitable, for example, for the oxidization of carbon monoxide to carbon dioxide, which makes it usable, among other things, in a fuel cell, in particular a polymer electrolyte membrane fuel cell (PEM), for protection of the anode catalyst against blocking by carbon monoxide.

Abstract: A novel method for fabricating diamond shells is introduced. The fabrication of such shells is a multi-step process, which involves diamond chemical vapor deposition on predetermined mandrels followed by polishing, microfabrication of holes, and removal of the mandrel by an etch process. The resultant shells of the present invention can be configured with a surface roughness at the nanometer level (e.g., on the order of down to about 10 nm RMS) on a mm length scale, and exhibit excellent hardness/strength, and good transparency in the both the infra-red and visible. Specifically, a novel process is disclosed herein, which allows coating of spherical substrates with optical-quality diamond films or nanocrystalline diamond films.