Room-Temperature Activation of Methane and Dry Re-forming with CO2 on Ni-CeO2 (111) Surfaces: Effect of Ce3+ Sites and Metal−Support Interactions on C−H Bond Cleavage

PABLO G. LUSTEMBERG; RAMÓN A. GUTIÉRREZ; SANJAYA SENANAYAKE; ZONGYUAN LIU; JAVIER CARRASCO; M. V. GANDUGLIA-PIROVANO; PEDRO J. RAMÍREZ; DAVID G. GRINTER; JOSÉ A. RODRIGUEZ

ACS Catalysis

SPRINGER/PLENUM PUBLISHERS

Lugar: New York; Año: 2016 vol. 6 p. 8184 - 8191

2155-5435

The results of core-level photoemission indicate that Ni-CeO2(111) surfaceswith small or medium coverages of nickel are able to activate methane at 300 K, producing adsorbed CHx and COx (x = 2, 3) groups. Calculations based on density functional theory predict a relatively low activation energy of 0.6−0.7 eV for the cleavage of the first C−H bond in the adsorbed methane molecule. Ni and O centers of ceria work in a cooperative way in the dissociation of the C−H bond at room temperature, where a low Ni loading is crucial for the catalyst activity and stability. The strong electronic perturbations in the Ni nanoparticles produced by the ceria supports of varying natures, such as stoichiometric and reduced, result in a drastic change in their chemical properties toward methane adsorption and dissociation as well as the dry reforming of methane reaction. The coverage of Ni has a drastic effect on the ability of the system to dissociate methane and catalyze the dry re-forming process.