metalloxid

Metalloxid is a broad term used in chemistry to describe compounds formed when metal elements bond with oxide. These materials are typically represented by the general formula MxOy, with metal cations balanced by oxide anions, and include simple binary oxides such as Fe2O3 and TiO2 as well as complex mixed-oxide systems like perovskites and spinels.

Structure and properties: Metalloxids display a wide range of crystal structures, from simple oxide lattices to defect-rich frameworks. They generally exhibit high thermal stability and chemical resistance. Their electrical behavior spans insulators, semiconductors, and conductors, depending on the metal, oxidation state, and presence of oxygen vacancies; optical properties also vary widely.

Synthesis and processing: They are prepared by solid-state reactions at high temperature, precipitation from metal salts, sol-gel methods, or vapor deposition, and by controlled oxidation of metals. Oxygen stoichiometry and vacancy concentration play key roles in tuning conductivity and catalytic activity.

Applications: Metalloxids are used as catalysts in oxidation reactions, in ceramics and refractories, as pigments (for example TiO2 and Fe2O3), and in electronics and sensors as dielectrics or semiconductors.

Safety and environment: Some metal oxides can pose health risks in dust form and may present environmental concerns if released improperly; safe handling and proper disposal are advised.

See also: Metal oxide semiconductor, ceramic oxide, oxide film.