Liu, Zongyuan; Lustemberg, Pablo; Gutiérrez, Ramón A.; Carey, John J.; Palomino, Robert M.; Vorokhta, Mykhailo; Grinter, David C.; Ramírez, Pedro J.; Matolín, Vladimír; Nolan, Michael; Ganduglia-Pirovano, M. Verónica; Senanayake, Sanjaya D.; Rodriguez, José A.

2017

September

Angewandte Chemie

In situ investigation of methane dry reforming on metal/ceria(111) surfaces: metal–support interactions and C-H bond activation at low temperature

Validated

()

Cobalt Ceroxid Dichtefunktionalrechnungen Methandissoziation XPS

Studies with a series of metal/ceria(111) (metal=Co, Ni, Cu; ceria=CeO2) surfaces indicate that metal–oxide interactions can play a very important role for the activation of methane and its reforming with CO2 at relatively low temperatures (600–700 K). Among the systems examined, Co/CeO2(111) exhibits the best performance and Cu/CeO2(111) has negligible activity. Experiments using ambient pressure X-ray photoelectron spectroscopy indicate that methane dissociates on Co/CeO2(111) at temperatures as low as 300 K—generating CHx and COx species on the catalyst surface. The results of density functional calculations show a reduction in the methane activation barrier from 1.07 eV on Co(0001) to 0.87 eV on Co2+/CeO2(111), and to only 0.05 eV on Co0/CeO2-x(111). At 700 K, under methane dry reforming conditions, CO2 dissociates on the oxide surface and a catalytic cycle is established without coke deposition. A significant part of the CHx formed on the Co0/CeO2-x(111) catalyst recombines to yield ethane or ethylene.

1521-3757

http://dx.doi.org/10.1002/ange.201707538

10.1002/ange.201707538