Metal oxides belong to a class of widely used catalysts. They exhibit acidic
or basic properties, which make them appropriate systems to be used as supports
for highly dispersed metal catalysts or as precursors of a metal phase or sulfide,
chloride, etc. Simple metal oxides range from essentially ionic compounds with
the electropositive elements to covalent compounds with the nonmetals. However,
taking into account the large variety of metal oxides, the principal objective of this
book is to examine only metal oxides that are more attractive from the catalytic
point of view, and most specifically transition metal oxides (TMO). In particular,
TMOusually exhibit nonstoichiometry as a consequence of the presence of defective
structures. The interaction of TMO with surfaces of the appropriate carriers
develop monolayer structures of these oxides. The crystal and electronic structure,
stoichiometry and composition, redox properties, acid–base character and cation
valence sates are major ingredients of the chemistry investigated in the first part
of the book. New approaches to the preparation of ordered TMO with extended
structure of texturally well defined systems are also included.