Flexible PVDF-BaTiO3 nanocomposites for pressure sensors

In this work, PVDF-BaTiO₃ composites were prepared using cryogenic high-energy ball milling (HEBM). PVDF-BaTiO₃ mixtures with different weight fractions of submicrometric BaTiO₃ particles were subjected to 1 h of effective milling. By applying pressure at 200 °C the resulting powder was molded in the form of relatively thin discs. Morphological and structural characterization of the materials was done using conventional techniques (DSC, FTIR, XRD, SEM). Piezoelectric characterization of the specimens was also carried out. Macroscopic tapping was used to induce a voltage in the materials. It was found that the output voltage decreases with the amount of BaTiO₃ particles. Finally, the piezoelectric behavior response of the samples was followed by an AFM microscope, the vertical deflection of the cantilever was obtained when an electrical signal was applied to the samples.