Spatially Confined PVDF/KNN‐CNTs Coaxial Nanofiber for Multifunctional Self‐Powered Intelligent Traffic Monitoring System

ABSTRACT Integrated real‐time monitoring of road traffic information is essential for the sustainable development of future intelligent transportation systems. However, existing monitoring systems often suffer from limited functionality, bulky equipment, and difficulties in data integration, which hinder comprehensive traffic information monitoring. Here, we propose a sensor design strategy based on spatially confined polyvinylidene fluoride (PVDF)/potassium‐sodium niobate (KNN)‐carbon nanotubes (CNTs) (PK‐C) coaxial nanofiber and investigate its applicability in integrated traffic information monitoring. The spatially confined coaxial structure and the localized conductive network formed by CNTs significantly enhance the overall performance of the PK‐C nanofiber. At a CNTs content of 0.5 wt.%, the crystallinity, content, and proportion of β‐phase reach 76.35%, 69.95%, and 91.62%, respectively. The piezoelectric constant, open‐circuit voltage, and short‐circuit current of the PK‐C nanofiber reach 692 pC/N, 11.93 V, and 1361.4 nA, respectively, demonstrating its ability to power low‐power devices. The developed PK‐C sensor shows a wide pressure monitoring range, high sensitivity, rapid response/recovery, and excellent durability over 1 000 000 cycles. Proof‐of‐concept tests demonstrate that the PK‐C sensor enables integrated real‐time monitoring of vehicle speed, axle load, type, offset, and traffic volume, highlighting its strong potential for lightweight traffic monitoring systems, weigh‐in‐motion, and fatigued‐driving detection in future intelligent transportation systems.