Impact of the support on the catalytic activity of Ag nanoparticles for soot combustion

This study investigates the catalytic activity for soot combustion of Ag nanoparticles dispersed on various supports showing different redox properties. Temperature programmed oxidation and isotopic exchange experiments were performed to assess impact soot/catalyst contact, oxygen partial pressure ageing toward activity. Three contact modes have been used clearly highlight performances: loose, tight supertight. Whatever support, in both loose modes, performances are linked with surface concentration which was found be high zirconia-based catalysts low ceria-zirconia. The ignition process occurs except supported Yttria-Stabilized Zirconia (YSZ), a pure ionic conductor, where only promote run-away reaction at higher temperatures. Catalysts based SiO2, ZrO2 YSZ exhibit remarkable hydrothermal stability as mode fairly similar after ageing.