Self-powered VO2 phase transition based on triboelectric nanogenerator

Abstract

The metal–insulator transition (MIT) of vanadium dioxide (VO₂), which involves significant changes in electrical, optical, and other properties, has attracted widespread attention. Here, we report a triboelectric nanogenerator (TENG)-based self-powered VO₂ phase transition. With the TENG-induced ionic gel gating, the hydrogen ion insertion/detachment in the VO₂ lattice can be modulated at room temperature to cause phase transitions that control light transmittance. The phase transition behavior is characterized by X-ray diffraction and Raman spectroscopy. Under the continuous power supply from TENG, the X-ray diffraction peak of VO₂ shifts, and the Raman intensities of characteristic peaks decrease, accompanied by a color change from brown to translucent. The electrical conductivity undergoes a significant change by two orders of magnitude and persists overnight, indicating an excellent duration of the phase transition. In addition, a raindrop TENG-induced VO₂ phase transition is demonstrated. The infrared transmittance of VO₂ is decreased dramatically by 28.1% due to the phase transition, achieving a heat preservation effect that holds promise for adaptive thermal insulation in smart windows during rainfall through raindrop power generation. This work has realized the TENG-based self-powered VO₂ phase transition, holding significant application potential in smart homes.