Piezoceramic materials have attracted much attention for sensing, actuation, structural health monitoring and energy
harvesting applications in the past two decades due to their excellent coupling between energy in the mechanical and
electrical domains. Among all piezoceramic materials, lead zirconate titanate (PZT) has been the most broadly studied
and implemented, in industrial applications due to its high piezoelectric coupling coefficients. Piezoceramic materials
are most often employed as thin films or monolithic wafers. While there are numerous methods for the synthesis of PZT
films, the sol-gel processing technique is the most widely used due to its low densification temperature, the ease at which
the film can be applied without costly physical deposition equipment and the capability to fabricate both thin and thick
films. However, the piezoelectric properties of PZT sol-gel derived films are substantially lower than those of bulk
materials, which limit the application of sol-gel films. In comparison, single crystal PZT materials have higher
piezoelectric coupling coefficients than polycrystalline materials due to their uniform dipole alignment. This paper will
introduce a novel technique to enhance the piezoelectric properties of PZT sol-gel derived ceramics through the use of
single crystal PbZr0.52Ti0.48O3 microcubes as an inclusion in the PZT sol-gel. The PZT single crystal cubes are
synthesized through a hydrothermal based method and their geometry and crystal structure is characterized through
scanning electron microscopy (SEM) and X-ray diffraction (XRD). A mixture of PZT cubes and sol-gel will then be
sintered to crystallize the sol-gel and obtain full density of the ceramic. XRD and SEM analysis of the cross section of
the final ceramics will be performed and compared to show the crystal structure and microstructure of the samples. The
P-E properties of the samples will be tested using a Sawyer-Tower circuit. Finally, a laser interferometer will be used to
directly measure the piezoelectric strain-coupling coefficient of the PZT sol-gel ceramics with and without PZT cube
inclusions. The results will show that with the integration of PZ0.52T0.48 crystal inclusions the d33 coupling coefficient
will increase more than 200% compared to that of pure PbZr0.52Ti0.48O3 sol-gel.
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