Microstructure and mechanical properties of lead zirconate titanate (PZT) nanocomposites with platinum particles

Fine platinum (Pt) particles-dispersed lead zirconate titanate, Pb(Zr,Ti)O-3 (PZT) nanocomposites were prepared by an electroless plating method which enabled to obtain a PZT nanocomposites homogeneously dispersed with fine platinum particles. Platinum particles with the size up to a few tens nanometer were precipitated on the surface of the PZT matrix. According to transmission electron microscope (TEM) observations, both the size and dispersion of the platinum particles may depend on the pH value of the aqueous platinum solution during electroless plating. After sintering, the platinum particles were found to be homogeneously dispersed in the PZT matrix. Fracture strength and toughness of the PZT nanocomposites were improved with retaining their electrical properties. Scanning electron microscope (SEM) observations revealed that the fracture mode of the PZT/platinum nanocomposites was transgranular, in contrast with the intergranular fracture mode of the monolithic PZT. This result suggests that the grain boundary structure of the PZT nanocomposites may be modified by the platinum, leading to improved mechanical properties.