fig3

Figure 3. Output performance of LF-TENG with ITO layer on Cu electrode and without ITO layer (control sample). (A) The comparison of LF-TENG voltage output with ITO layer on Cu electrode and without ITO layer (control sample); (B) Bridge rectifier circuits used to convert the AC to DC; (C) The comparison of LF-TENG DC output with ITO layer on Cu electrode and without ITO layer (control sample); (D) Output voltage and current at ohmic loads of 1 kΩ to 2 GΩ; (E) Power density (P = V²/RA), where V, R, and A are the voltage, resistance, and contact area of LF-TENGs, respectively; (F) Charging voltage of 0.4, 1.0, 2.2, and 3.2 μF capacitors. AC: Alternating current; DC: direct current; ITO: indium tin oxide; LF-TENG: laminated flexible-triboelectric nanogenerator.