Electronic behavior of carbon clusters/hafnium oxide composite material

An alternating hafnium-O-phenylene hybrid copolymer was calcined under the reduced pressure at 400–700 °C to obtain black-colored materials. XRD and TEM analyses showed that the calcined materials were composed of carbon clusters with the diameters of 20 nm and hafnium oxide particles with the diameters of a few nm. ESR spectral examinations revealed that the calcined materials formed a stable cation radical on the carbon clusters and exhibited an oxidation–reduction function. When Au particles were supported on the material, an efficient oxidation–reduction function was found to appear.