有機金属化合物の加圧熱分解による機能性炭素材料の合成

Abstract

Carbon composites of controlled morphology dispersed with finely metal or metallic compound particles can be synthesized in high carbon yield by the pressure pyrolysis of organometallic polymers. The size and the morphology of the carbon matrix can be controlled by the selection of the pyrolysis conditions as well as the amounts of coexistent water and the metal concentration in copolymers. Organometallic polymers undergo pressure pyrolysis affording the liquid phase of oligomers, which is responsible for the morphology of carbons through liquid-liquid microphase separation. Supercritical water affected the liquid phase separation during pyrolysis yielding carbon spherulite of about several micrometers dispersed with ferrite particles less than 100 nm. The magnetic properties of metal-dispersed carbon are attributed to the crystallinity and the particle size of the metals, which have been foundto depend strongly on the properties of both the carbon-metal bond of organometallic compounds and the carbon-carbon bond of the polymer matrix. Metal-dispersed carbon composites of controlled morpholgy have potentials of many applications for magnetic materials, catalysts and pigments and so on. This processing affords a novel method for producing carbon nano-composites with controlled microstructure and morphology.