PFM Characterization of Piezoelectric PVDF/ZnO-N Anorod Thin Films

The present work reports the development and the piezoelectric characterization of nano-engineered thin-films of Polyvinylidene Fluoride (PVDF) and vertical array of zinc oxide nanorods (ZnO-NRs). In particular, the piezoelectric response of the produced samples was investigated by evaluating the piezoelectric coefficient $(\mathrm{d}_{33})$, through Piezoresponse Force Microscopy (PFM). We compared the piezoelectric response of three different samples: a neat PVDF thin-film, an array of vertically oriented ZnO-NRs and an array of vertically oriented ZnO-NRs embedded in PVDF. We tested two types of substrates: a flexible substrate namely PET-ITO and a rigid substrate namely ITO coated glass. The highest piezoelectric response was found to be exerted by the hybrid system made of vertically aligned ZnO-NRs array embedded in PVDF on PET-ITO substrate, showing a piezoelectric coefficient, as high as 14.91 pm/V.