From anti-counterfeit polymer materials to dual-mode visualization sensor based on triboelectric nanogenerator

With the rapid development of flexible electronics and intelligent sensing technologies, triboelectric nanogenerators (TENGs) have garnered significant attention in the field of human-computer interaction due to their ability to convert human mechanical energy into visible light. However, traditional TENG devices often face limitations such as single functionality, low transparency, and insufficient mechanical properties, which hinder their further application in high-end fields. To address these challenges, this study proposes a simple and low-cost fabrication method, utilizing a solution-drying process to prepare ZnS:Cu@TPU films. The morphology, structure, light transmittance, and mechanical properties of the films were systematically characterized. The films exhibited excellent tensile properties (with a maximum strain of 1300% and a corresponding tensile strength of 2.5   MPa) and high light transmittance. Additionally, the films displayed different colors under ultraviolet or infrared light irradiation. Based on the ZnS:Cu@TPU films, a contact-separation triboelectric nanogenerator (ZnS:Cu@TPU-TENG) was constructed, demonstrating a high output voltage of 240   V and remarkable stability. Furthermore, the ZnS:Cu@TPU-TENG can convert touch information into both visible light signals and electrical signals, enabling real-time touch imaging and handwriting pressure sensing, thereby functioning as a dual-mode visual sensor. This study highlights the immense potential of ZnS:Cu@TPU-TENG in high-end applications, particularly in the fields of intelligent sensing, flexible electronics, anti-counterfeiting technologies, and interactive human-machine interfaces.