In Situ Investigation of Methane Dry Reforming on Metal/Ceria(111) Surfaces: Metal–Support Interactions and C−H Bond Activation at Low Temperature

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.Fil: Liu, Zongyuan. Brookhaven National Laboratory; Estados UnidosFil: Lustemberg, Pablo German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Gutiérrez, Ramón A.. Universidad Central de Venezuela; VenezuelaFil: Carey, John J.. University College Cork Lee Maltings; IrlandaFil: Palomino, Robert M.. Brookhaven National Laboratory; Estados UnidosFil: Vorokhta, Mykhailo. Charles University; República ChecaFil: Grinter, David C.. Brookhaven National Laboratory; Estados UnidosFil: Ramírez, Pedro J.. Universidad Central de Venezuela; VenezuelaFil: Matolín, Vladimír. Charles University; República ChecaFil: Nolan, Michael. University College Cork Lee Maltings; IrlandaFil: Ganduglia Pirovano, Maria Veronica. Consejo Superior de Investigaciones Científicas; EspañaFil: Senanayake, Sanjaya D.. Brookhaven National Laboratory; Estados UnidosFil: Rodriguez, José A.. Brookhaven National Laboratory; Estados Unido