Piezoelectric force microscopy study on zinc tin oxide nanowires

Self-powered sensor devices could find widespread application to monitor personal health, automobiles or buildings. One of the most ubiquitous form of energy on which these devices could rely is vibrational energy. To convert this energy into electrical energy, the research is focusing on piezoelectric materials. Examples of these materials are ZnO or Zinc Tin Oxides (ZTO). Modelled into nanowires and incorporated into an elastomer at the University of Lisbon, these materials have been demonstrated to result in macroscopically efficient energy conversion. In this work, I use Piezoelectric Force Microscopy to characterize the piezoelectric response of a single ZTO nanowire, namely, to measure the component d33 of its piezoelectric strain tensor. P(VDF-TrFE) thin film, i.e. a material with well characterized piezoelectric proprieties, is used to calibrate the instrument sensitivity. The value I obtain for the d33 of the ZTO nanowire is 23.70±0.04pm/V. In order to use it as a reference, I perform a characterization also for a ZnO nanowire. The value I obtain is 10.36±0.03pm/V. The value for the ZTO nanowire is therefore about double that of the ZnO. This result certifies ZTO nanowires as good candidates for energy conversion in future self-powered devices.