Characteristic features and applications of catalysis by gold

摘要

Gold has been neglected as a catalyst, however, gold nanoparticles strongly interacted with the metal oxide support exhibit surprisingly high catalytic activity and selectivity for low-temperature CO oxidation and propylene epoxidation, respectively. There are three characteristic features of such gold catalysts; the performance markedly depends on preparation of methods because it is defined by the contact structure of Au particles, type of metal oxides, and the size of Au particles. Secondly, apparent activation energy is very low and smaller than 40 kJ/mol, indicating that gold catalysts are advantageous in low-temperature operation, which is often preferred in environmental applications. Thirdly, the catalytic activity is usually improved by the co-presence of moisture. These properties of supported Au catalysts lead to applications to indoor air quality control, pollutant emission control (dioxin, NOx), H_2 energy-related reaction, and new chemical processes.