Cobalt(II,III) oxide, or Co3O4, is a black, inorganic compound composed of cobalt in two oxidation states: +2 and +3. It is commonly used as a catalyst in various chemical reactions and is also found in batteries, ceramics, and pigments due to its stability and unique properties. Co3O4 can be synthesized through several methods, including thermal decomposition and solid-state reactions. It has a spinel crystal structure, which contributes to its magnetic and electronic characteristics. Additionally, Co3O4 is studied for its potential applications in energy storage and conversion technologies.