*2.3. Preparation of Au-TNR/PVDF Nanocomposites*

Au-TNR/PVDF nanocomposites containing Au-TNR fillers with different *f* Au and *f* TNRs values were prepared through liquid-phase-assisted dispersion and hot-pressing methods. First, Au-TNR hybrid nanoparticles and the PVDF powder (Mw ~ 534,000, Sigma-Aldrich) were mixed by ball-milling with ZrO2 in ethanol for 3 h. Second, the mixture was dried at 80 ◦C to evaporate ethanol, after which the mixed powder was pressed at 200 ◦C for 30 min at 10 MPa. Finally, the Au-TNR/PVDF nanocomposite sample, with a diameter and thickness of ~12 mm and ~0.5–1 mm, respectively, was obtained at room temperature. Au-TNR/PVDF nanocomposite samples with *f* Au-TNRs = 0.094, 0.216, 0.294, 0.383, 0.492, and 0.624 are referred to as Au-TNRs/PVDF-1, Au-TNRs/PVDF-2, Au-TNRs/PVDF-3, Au-TNRs/PVDF-4, Au-TNRs/PVDF-5, and Au-TNRs/PVDF-6, respectively. The separated volume fractions of Au and TNRs for each composite sample are listed in Table 1.


**Table 1.** Volume fraction of Au (*f* Au), TNRs (*f* TNRs), Au-TNRs (*f* Au-TNRs), ε , tanδ, and σac at 1 kHz and room temperature for nanocomposites with varying filler amounts.
