Catalysis Chemistry of Crystalline Complex Metal Oxide Catalysts

Crystalline metal oxide catalysts have contributed to the development of various catalytic reactions for many years and are expected more by the way of exploring new structural oxide solids and by sophisticated designing based on elemental complexation. However, many difficulties in determining the actual surface structure directly involved in catalytic reaction have always been a concern in the understanding of real catalytic functions. Various aspects relating to this issue are outlined. Crystalline porous complex metal oxide constructed with discrete metal oxide clusters having specific catalytic properties and also with metal polyhedra in the coordinatively unsaturated state, both of which are also important for catalytic function, is proposed as an ideal solid-state catalyst, because this structural state can completely avoid any concern about the surface state of a solid.