The CO oxidation is very important of practical for the control environmental pollution, the purification of industrial emissions, and the CO preferential oxidation in fuel cell. Hopcalite catalysts (mainly composed of MnOx and CuO) and supported Pt, Pd, Ru, Rh catalysts are both the important catalysts for CO oxidation. However, all of them have high activity only at relatively high temperature. Since the exciting finding by Haruta and co-workers that supported gold catalysts with high activity even at temperature below 0 oC, various Au-containing catalysts were investigated and found to be active for low-temperature CO oxidation. However, most of them exhibit very poor stability at anti-sintering. Therefore, searching for new catalysts which have both excellent activity and ultrastability become an important task. To achieve this aim, many approaches had been conducted by many groups, for example, using the mixed oxides as support, modifying the surface of the support by PO43-, NO3-, SO42- or developing new supports like metal phosphates. These approaches, to some degree, improved the stability of the catalysts to resist sintering at high temperature, but actually made them more easily deactive on stream.Here, fortunately, we found one kind of novel hydroxyapatite(HAP)-based catalyst Au/Fe3O4HAP which not only exhibits high activity even after 400 oC sintered, but also stable on stream (data is not shown here). Comparing with Au/HAP and Au/Fe3O4 prepared by the same method and the Au/Fe2O3 standard, Au/Fe3O4HAP exhibits the highest activity and stability. The obviously relaxative 57Fe M�ssbauer spectra imply that Fe3O4 particles are very small. Furthermore, the little change of the spectra indicates that Fe3O4 is very stable after encapsulated by HAP, gold deposition-precipitation and even the catalytic reaction.

Highly efficient and stable Au/Fe<sub>3</sub>O<sub>4</sub>HAP catalyst for CO oxidation

239th National Meeting (2010)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.