Methanation on mass-selected Ru nanoparticles on a planar SiO2 model support: The importance of under-coordinated sites

• Mass-selected Ru nanoparticles were deposited onto planar SiO2 support and probed for the methanation reaction.
• Loss in TOF was found to be size-dependent.
• Carbon poisoning and sintering were ruled out as a cause for TOF loss.
• Surface restructuring was invoked as a cause for the loss in TOF.

Mass-selected Ru nanoparticles were deposited onto planar SiO2 support and their capability for the methanation reaction investigated. The catalytic activity for the methanation reaction at 100 mbar under hydrogen rich conditions (1:99 CO/H2 ratio) was measured as a function of particle size. We found that the Turnover Frequency increased with nanoparticle diameter in the range 4–10 nm.As the TOF decreases over reaction repetition, we investigated the possible reasons and ruled out carbon deposition as a cause for activity loss. As no particle sintering was observed, we invoked surface restructuring as a possible cause.

Size-selected Ru nanoparticles display turn over frequency (TOF) decrease as the methanation reaction is repeated. The loss in TOF is attributed to particles surface restructuring.Figure optionsDownload high-quality image (74 K)Download as PowerPoint slide