Characterizations of Pt/CeO2 during model redox sequences

MICROSCOPIE+ATARI:CARE:ECI2D+GFE:MAO:FCA:CGE:SLO:PVEInternational audienceThe shape, size and electronic properties of Pt nanoparticles supported on ceria have been tailored during model redox sequences based on successive H2 (reduction) and O2 (oxidation) 1 hour treatments at moderate temperatures (250 °C and 500 °C). Raft shaped Pt nanoparticles of around 1 nm size are produced on the surface, in strong interaction with ceria, then boosting the oxygen transfer from the oxide towards Pt. In situ techniques establish the presence of Pt cations in an intermediate oxidation state, probably Pt2+, in interaction with peroxo oxygen species