Fig. 5: In situ environmental transmission electron microscopy (ETEM).
From: Tracking the dynamics of catalytic Pt/CeO2 active sites during water-gas-shift reaction
The Supplementary Movies 1–9 show the dynamics of active sites on Pt/CeO2 catalysts under different conditions. a1 and a2 snapshots of ETEM image of Pt/CeO2-rod catalyst after 0.40 Torr O2 pretreatment at 400 °C for 30 min. b1 and b2 snapshots of ETEM image of Pt/CeO2-rod catalyst after 0.40 Torr H2 pretreatment at 300 °C for 30 min. c1 and c2 snapshots of ETEM image of Pt/CeO2-rod catalyst under reaction conditions with 0.10 Torr CO and 0.20 Torr H2O at 300 °C. d1 and d2 snapshots of ETEM image of Pt/CeO2-cube catalyst after 0.40 Torr O2 pretreatment at 400 °C for 30 min. e1 and e2 snapshots of ETEM image of Pt/CeO2-cube catalyst after 0.40 Torr H2 pretreatment at 300 °C for 30 min. (f1 and f2) snapshots of ETEM image of Pt/CeO2-cube catalyst under reaction conditions with 0.10 Torr CO and 0.20 Torr H2O at 300 °C. g1 and g2 snapshots of ETEM image of Pt/CeO2-oct catalyst after 0.40 Torr O2 pretreatment at 400 °C for 30 min. h1 and h2 snapshots of ETEM image of Pt/CeO2-oct catalyst after 0.40 Torr H2 pretreatment at 400 °C for 30 min. i1 and i2 snapshots of ETEM image of Pt/CeO2-oct catalyst under reaction conditions with 0.10 Torr CO and 0.20 Torr H2O at 300 °C. Scale bars are 2 nm. To minimize electron beam effect, the dynamics of catalyst were recorded after O2 and H2 pretreatment for 30 min. The dynamics of catalyst under reaction conditions were recorded after reactants were introduced into the system. The snapshots were selected when the structural reconstruction occurred. Therefore, 0 s and 10 s do not represent the 0 s of starting time and the 10 s of the reaction.
