Dresden 2014 – wissenschaftliches Programm
O 9.7: Vortrag
Montag, 31. März 2014, 12:00–12:15, PHY C 213
Simulation of Ni/CeO2 surfaces for CO2 catalysis — •Konstanze Hahn1 and Jürg Hutter2 — 1University of Cagliari, Monserrato, Italy — 2University of Zurich, Zurich, Switzerland
Combined metal-metal oxide systems are important materials for numerous technological applications such as microelectronics, photovoltaics, gas sensors and in particular in oxide-supported metal catalysts. Deposition of small metal particles on metal oxides such as Al2O3, CeO2 and TiO2 has led to enhanced catalytic activity, for example, for the water gas shift reaction or CO oxidation. Metal oxide supported materials are also promising catalysts for hydrocarbon production from CO2, a reaction process interesting for alternative energy production since it provides high energy density fuel from CO2 which is omnipresent in our environment. In fact, CeO2-supported Ni particles have proven to be promising materials for the activation of methanation of CO2. Here, density functional theory within the Gaussian and plane waves formalism has been used for the simulation of Ni cluster formation on CeO2(111) surfaces. Stabilization of Ni particles has been observed with increasing cluster size up to ten atoms. It has been found that O diffusion from the subsurface layer of CeO2(111) to the surface layer is facilitated in the presence of Ni particles on the surface. Furthermore, the adsorption and dissociation of CO2 has been investigated on clean CeO2(111), on non-supported Ni clusters in the gas phase and on the Ni/CeO2(111) system. This study gives fundamental insight into the metal-metal oxide interactions and its function for CO2 catalysis.