THE POSSIBLE ROLE OF SURFACE-DIFFUSION IN THE SYNCHRONIZATION OF AUTOOSCILLATIONS OF THE RATE OF CO OXIDATION ON METAL PARTICLES SUPPORTED ON INERT MATERIALS

A model comprising metal particles of two types, MI and MII, as separa te strips almost-equal-to 10(3) angstrom width, divided by a support m aterial, 500 angstrom width, is considered. The reaction proceeds acco rding to a five-stage mechanism with two sets of rate constants for th e particles of each type. CO diffusion between metal species and the s upport material in both directions and CO adsorption-desorption on the support material are taken into account. The calculations show that C O surface diffusion is able to provide the complete synchronization of autooscillations of the reaction rate for MI and MII particles with d ifferent CO-metal bond energies. This means that the entire MI + suppo rt material + MII surface acts as an integrated system. At a limited r ate of diffusion, the synchronization does not function and quasichaot ic oscillations are observed.