Mutually Influenced Stacking and Evolution of Inorganic/Organic Crystals for Piezo-Related Applications

Sections 5.1–5.6 review certain piezoelectric nitride films (e.g., ZnSnN2 and TixAl1−xN) fabricated through combinatorial reactive sputtering, and oxide films (e.g., ZnSnO3, BaZnO2, and BiFeO3) through hydrothermal syntheses. To enhance the piezoelectric responses, the morphologies of these films were adjusted into one-dimensional nanorods/or nanowires, and further tailored into periodic arrays by the optimization of various parameters during fabrication processes. Their great promise for the use in piezoelectric-related applications was illustrated, including piezotronic/piezophotoelectronic effects, piezophotodegradation, and piezophotoelectrochemical reactions. In addition to ceramic piezoelectrics, the unique piezoelectric features and working principals of amorphous and semicrystalline polymer elastomers have been reviewed. For the polycrystalline polymer piezoelectrics to yield superior performances, several strategies able to increase available polarizability have been discussed, including the increase in the fractions of ferroelectric crystals, the improvement of crystal alignment, and also the enhancement of interfacial polarization. Hence, this chapter elucidates basic directions to harvest the synergistic coupling of polymer and inorganic piezoelectrics in Sections 5.7–5.8, and explains why mutually influenced stacking and evolution of inorganic/organic crystals are helpful to enhance piezo-related performances and innovative roles of piezocomposites.