Catalysis: Reactivity and Structure

Fundamental Studies of Well-Defined Surfaces of Mixed-Metal Oxides: Special Properties of MO_x/TiO₂(110) {M = V, Ru, Ce, or W}

In this article, we give an overview of recent work focused on investigating the properties of clusters or nanoparticles of VO_x, RuO_x, CeO_x, and WO_x on TiO₂(110). Mixed-metal oxide catalysts which contain submonolayer amounts of VO_x, RuO_x, CeO_x, or WO_x dispersed on titania are quite important in industrial applications and the TiO₂(110) substrate is one of the most studied oxide surfaces. As we will show, experiments with a well-defined substrate allow better control of the structural or morphological properties of the mixed-metal oxides, making feasible a systematic study of these systems. Thus, one can explore relationships between their structural, electronic, and chemical properties and improve the understanding of the more complex powder catalysts. Experiments using the modern techniques of surface science are giving exciting insights into phenomena responsible for the behavior of mixed-metal oxides at the nanometer range. The ability to control the structure of a mixed-metal oxide at the nanometer level opens new approaches for the design of novel catalysts.

Ref: Stacchiola, D.J., Senanayake, S.D., Liu, P., and Rodriguez, J.A. Chemical Reviews, 2013. 113(6): p. 4373-4390. DOI: 10.1021/cr300316v