The electrification mechanism of an oxide particle in a bath was analyzed. The zeta-potentials of various oxide particles in an acetone bath were found to be positive. The data suggested that H+ ions are generated in an acetone bath containing a small amount of added I2 and H2O by the keto-enol equilibrium reaction and then adsorbed on the oxide resulting in positively charged particles. The adsorption of H+ ions was assumed to be of the type of mono-molecular adsorption. Moreover, the electrodeposition flocculation mechanism for the particle was also investigated. On the basis of a relation of electrophoretic current with depositing time well described by the Cottrell equation, it was suggested that the electrochemical reaction proceeds on the cathode substrate surface and that the rate-determining step arises from the diffusion of H+ ions in the deposited film.

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A preparation method of a superconducting oxides, YBa2Cu3O7-δ, coating on austenitic stainless steel by electrophoretic deposition at high voltages has been investigated in order to increase the J c value. Without a buffering layer, Ni, Cr, and Fe atoms diffused from the substrate to the superconductor phase. It was found that ZrO2 and Ag layers coated on the substrate as the buffering layer restrain the diffusion of the metals. Consequently, high density YBa2Cu3O7-δ superconductor coating could be obtained at high voltage depositions, therefore, it indicated that high J c samples can be prepared by this method.

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