Flexible Pressure Sensors and Their Applications in Wearable Electronics

With the development of modern technology, flexible human-machine interaction, artificial intelligence, portable detection, and other emerging fields have been built up. The demand for high flexibility in these fields leads to flexible pressure sensors getting more and more attention. Using flexible materials can enable them to realize the pressure sensing function while giving them lighter weight, smaller size, and better deformation ability. These characteristics make flexible pressure sensors can be widely used in emerging fields and have more longterm development potential. In recent years, many technologies have been devoted to improving the performance of flexible pressure sensors. Among them, microstructure engineering is the most significant for high-performance flexible sensors. This review focuses on the rapid development of flexible pressure sensors and the microstructure of high-performance flexible sensors. This article describes four sensing mechanisms: capacitive, resistive, piezoelectric, and triboelectric. Besides, the microstructure system, which can improve the sensitivity of capacitive flexible pressure sensors, is discussed comprehensively. In addition, the current applications of the capacitive flexible pressure sensor are introduced. Furthermore, this article discusses prospects for developing direction and application fields of high-performance flexible pressure sensors according to some currently developed microstructure technologies. The research in this review has essential foreshadowing significance and reference value for developing flexible pressure sensors in various intelligent fields in the future.