**Perovskite-Based Mesostructures and Related Composites — Influence Exerted by Morphology and Interface**

Guilhermina F. Teixeira, Rafael A. Ciola, Walter K. Sakamoto and Maria A. Zaghete

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/60654

### **Abstract**

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The present work seeks to report about the properties of lead-free NaNbO3 particles with different morphology (cubic-like and fiber-like particles) and their application in composites with poly(vinylidenefluoride) (PVDF) polymer. The composites are obtained using a range of varying volume fractions of NaNbO3 particles (30%, 40%, 50% and 60%). The best conditions for obtaining the NaNbO3 particles as well as the composites have been thoroughly studied. It was observed that the highest volume fraction of NaNbO3 particles undermined the flexibility of the composites. The tran‐ sition percolation phenomenon, commonly known as percolation threshold, was calculated as a function of the dielectric constant and conductivity of the composite. The composites exhibit piezoelectric and ferroelectric properties and both are found to improve by anisotropy of the NaNbO3 particles.

**Keywords:** lead-free composites, piezoelectricity, ferroelectricity, anisotropy, perco‐ lation threshold
