Suspension stability of Pb(Zr0.58 TiO0.42)O3 nano-particles during electrophoretic deposition

It is well known that electrostatic stability refers to the stability of the suspension. The zeta potential is an important parameter of the dispersion stability and a measurement of the interaction strength among the colloid particles. In general, the charged ultra fine particles are moved randomly in the suspensions by the Brownian motion, and then easily coagulated by collision among particles. The nano-sized particles should be more heavily agglomerated than that of the submicron particles due to the influence of applied forces. The fact that agglomeration must be heavily formed by an applied force during electrophoretic deposition (EPD). The agglomeration can cause undesirable large pores during further drying. Therefore, the agglomerates should be avoided to prepare a homogeneous microstructure. The stabilized suspensions were prepared by using PZT nano-particles in a solvent of methanol. The EPD process was conducted by variation of an applied DC field and a distance between electrodes and deposition time. The agglomeration rate was measured an increasing the particle number concentration. The homogeneous microstructure of deposited films resulted from the conditions of 30 V, 1.5 cm, and 600 s, respectively. (C) 2007 Elsevier Ltd. All rights reserved.