Microstructure and Optical and Piezoelectric Properties of Polyvinylidene Fluoride/ZnO Nanowires for Tactile Sensors.

Polyvinylidene fluoride (PVDF)/ZnO nanowire arrays were prepared on polydimethylsiloxane (PDMS) substrates for piezoelectric pressure sensor applications by the chemical bath deposition method. The effects of three different catalysts, namely, NaOH, NH₄OH, and C₆H₁₂N₄ (HMT), on the crystal structure, surface structure, and optical characteristics of ZnO nanowires have been studied. The piezoelectric sensing properties of pressure sensors formed by coating PVDF on ZnO nanowires were also studied under different forces. The results showed that the ZnO nanowires obtained with HMT have a hexagonal wurtzite crystal structure with a good c-axis (002) preferred orientation, as well as the largest length of 5800 nm and a length-to-width ratio of 72.5. The maximum sensitivity of the sensor with the ZnO nanowire length of 5800 nm is 61.1 mV/N. In addition, the sensor exhibits an optimized linear response within the applied pressure range of 0.1-1.2 N. [ABSTRACT FROM AUTHOR]