PECULIARITIES OF COBALT NANOMETER-SCALE PARTICLE NUCLEATION ON AN ALUMINA SURFACE

The process of Co cluster formation in the cryochemical synthesis of the Co/Al2O3 system has been studied. The samples of metal powders and Co/Al2O3 systems have been investigated by the transmission electron microscopy (TEM) method. It is shown that the size of particles formed under conditions of cryochemical synthesis and subsequent preparative manipulation depends greatly on such parameters as temperature, duration of operations, and peculiarities of external influences on the system. It is ascertained that the conditions of controlled Co(C6H5CH3)(2) decomposition carried out under direct contact with alumina, cryothermostating, and ultrasonic irradiation are conducive to the reduction of Co cluster size in the Co/Al2O3 systems obtained. (C) 1995 Academic Press, Inc.