Photoactive ferroelectric composite of g-C₃N₄@BaTiO₃ in P(VDF-TrFE) polymer for enhanced triboelectric power generation

Robust design of a photoactive composite film with ferroelectricity is a promising strategy to enhance triboelectric power output via coupling of photocarrier and ferroelectric dipole. Herein, we reported the fabrication of a photoactive ferroelectric composite film-based triboelectric nanogenerator (Photo-FE@TENG), comprising a chemically bonded visible-light responsive g-C₃N₄@BaTiO₃ (CN@BT) in a ferroelectric P(VDF-TrFE) polymer. The CN@BT nanoparticles in P(VDF-TrFE) polymer reduce the bandgap and increase the workfunction, remnant ferroelectric polarization, and dielectric constant. Under the simultaneous application of mechanical vibration and blue-light illumination, the poled composite-based Photo-FE@TENG generates boosted triboelectric outputs with current density of 2.59 μA/cm² and power density of 0.56 mW/cm², far exceeding previous Photo-TENGs. The triboelectric outputs are highly stable under excessive mechanical vibration and light illumination. Such behaviors are attributed to the optimized CN@BT concentration in P(VDF-TrFE) polymer, the enhanced band-bending induced photocarrier movement, and the enhanced dielectric constant induced charge trapping ability. We demonstrated that the poled composite could generate sufficient power to lighten 200 white LEDs, operate a scientific calculator, a thermo-hygrometer, and a wristwatch. This study provides an innovative approach to increase triboelectric power through the interaction of photocarriers and ferroelectric dipoles and provides a significant advance for the self-powered electronic devices in dark environments.