Fig. 2: Dynamic structural response and behavior of the Pt/CeO2 catalyst.
From: Dynamic structure of active sites in ceria-supported Pt catalysts for the water gas shift reaction
a1–a6 Images of the Pt/CeO2 catalyst at 200 °C in CO gas. b1–b6 Images of the Pt/CeO2 catalyst at 200 °C in WGS reaction conditions. a1/b1 shows the catalyst (close to the mean size of 1.7 nm) in a single 150 millisecond frame (ms/frame). Time-averaged image series from sequential 1.5 s intervals are shown in Figs. a2–a5 and b2–b5. The CeO2-supported Pt nanoparticle adopts a bent, facetted morphology in the WGS condition, which is highlighted by the dashed outline and facet labels. Dynamic structural fluctuations are seen at perimeter sites as indicated by the yellow arrow. a6/b6 show the time-averaged image over the entire 6 s movie for each condition. The corresponding in situ TEM movies can be found in Supplementary Movie 1 and 2. The same Pt nanoparticle is shown in all frames. The behavior exhibited by the Pt nanoparticle in Fig. 2 is typical of the many observed during the in situ TEM experiment. Additional images from a different particle, for example, are shown in Supplementary Fig. 5.
