fig5

Figure 5. PFM measurements of the piezoelectric responses of (A-D) PVDF and (E-H) CPB/PVDF nanocomposite fiber films at a 4 wt.% CPB loading. (A, E) Topographic images of films. (B, F) Corresponding vertical amplitude and (C, G) lateral amplitude piezoelectric responses obtained at an ac voltage of 5 V of the same area shown in (A, E). (D, H) Piezoelectric response histograms from vertical amplitude values. The scan area is 2 × 2 μm².