Effect of the lattice oxygen mobility on the activity of Gd-doped ceria promoted with pt in syngas generation from methane at short contact times

Abstract

The activity of Pt/Ce 1-x Gd x O 2-y samples in steam and dry reforming of methane at short contact times correlates with the lattice oxygen mobility. For the partial oxidation of methane (POM), the oxygen mobility should be optimized to prevent methane combustion.

Nanostructured, Gd-Doped Ceria Promoted by Pt or Pd: Investigation of the Electronic and Surface Structures and Relations to Chemical Properties

“…Chemical Behavior with Respect to Catalytic Conversion of Methane. Recently it was shown that nanostructured cerium dioxide doped with different rare earth elements and promoted with noble metals may serve as an efficient catalyst for synthesis gas generation via selective oxidation as well as steam or dry reforming of methane. , The syngas yield was found to depend on the lattice oxygen mobility, which in turn can be tuned in the nanostructured ceria system by the appropriate choice of the kind and amount of dopant ions. − To further investigate the catalytically relevant redox properties of the Gd-doped ceria, additional temperature-programmed- reduction experiments have been performed using 1% CH 4 in He as a reducing agent.…”

“…This opens new possibilities to further modify and improve the materials with respect to possible catalytic applications. Recently, we reported on nanostructured ceria doped with Sm, Bi, Pr, , and Gd , prepared by the so-called “Pechini method” . The materials exhibit high oxygen ion conductivity with the lattice oxygen mobility depending on the kind and amount of dopant ions.…”

“…The materials exhibit high oxygen ion conductivity with the lattice oxygen mobility depending on the kind and amount of dopant ions. Furthermore, the reactivity of the lattice oxygen in the interaction with methane can be modified by promotion of the doped ceria with Pt or Pd. − This is quite important for possible catalytic applications such as methane conversion into synthesis gas.…”

“…Furthermore, the reactivity of the lattice oxygen in the interaction with methane can be modified by promotion of the doped ceria with Pt or Pd. [15][16][17][18][19] This is quite important for possible catalytic applications such as methane conversion into synthesis gas.…”

Methane oxidation over nanocrystalline Ce0.45Zr0.45La0.10O2-δ/Pt and Ce0.9Sm0.1O2-δ/Pt anodes

“…The mobility of oxygen ions in the ceria lattice may play an important role in the catalytic performance influencing oxygen supply from the bulk to active surface centers and the kinetics of redox process. For instance, an inverse correlation between lattice oxygen mobility and selectivity towards POM was observed for Ce 1Àx Gd x O 2Àd fluorite-type solid solutions [23]. Higher oxygen mobility in Ce 0:9 Sm 0:1 O 2Àd compared to that in Ce 0:45 Zr 0:45 La 0:10 O 2Àd [19] should promote the activation of oxygen ions at the platinum/ oxide interface and result in faster oxidation of methane and/or partial oxidation products.…”