Effect of particle size and morphology on the performance of BiFeO3-PDMS piezoelectric generators

Piezoelectric oxide-polymer composite generators have attracted increasing attention for sensoring and energy-harvesting applications. In this work, the effect of the size and morphology of BiFeO3 (BFO) particles on the performance of BFO-poly(dimethylsiloxane) (PDMS) composite generators is revealed. Three kinds of BFO particles-nanoparticles, microspheres, and microplates-were synthesized via solution synthesis routes and applied to BFO-PDMS composite films. The BFO microplates were found to be preferentially oriented along the pseudocubic <100> direction in the composite film due to their anisotropic morphology, while the nanoparticles and microspheres were not oriented. The composite film fabricated from the BFO microplates generated a higher open-circuit voltage in response to an applied compressive force compared to the other films. The effect of the particle size and morphology on the open-circuit voltage was discussed in terms of the dispersion and polarized states of the particles.