Rose-Petal Inspired High-Performance Triboelectric Nanogenerators for Real-Time Vehicular Speed Monitoring

Biomimetic triboelectric nanogenerators (TENGs) with friction layers of micro-structured polydime-thylsiloxane (PDMS) and nanostructured aluminum have been reported. Microstructures on the PDMS layer have been developed using the rose petal as the primary mold, whereas the water-assisted oxidation (WAO) process has been utilized to prepare a nanostructured aluminum surface. TENG with aforementioned films generates an open-circuit voltage of ~400 V, a short-circuit current of $\sim 40 ~\mu \text{A}$ , and a high power density of 6.67 $\text{W}\cdot \text{m}^{-{2}}$ . The high-performance reliability and stability of TENGs are inferred from their identical electrical characteristics over 20 000 impact cycles and up to 120 days, respectively, which suggest a high degree of robustness. Furthermore, the proposed micro-structured TENGs have been explored for vehicular speed determination and incorporated as self-powered sensing elements in a real-time vehicular speed monitoring system. This microcontroller-based monitoring system displays the speed of the interacting vehicle and related messages of normal and over-speed cases. This work illustrates the huge prospects of TENGs as the fundamental constituents of self-powered real-time traffic monitoring and rider-alert systems, having excellent robustness, precision, and efficiency.