Flexible Thermoelectric Materials and Devices for Sensing Applications

Abstract

Given the explosive advancement of artificial intelligence and the Internet of Things, flexible, portable, sustainable and maintenance-free sensors, are increasingly demanded. Align with that, the development of efficient energy harvesting devices to power these sensors is crucial and has aroused extensive attention recently. Flexible thermoelectric devices have emerged as promising candidates because they are capable of converting temperature differentials into voltage directly with flexibility, absence of vibration, long service life, and seamless integration with various multifunctional miniaturized electronics. Additionally, flexible thermoelectric (FTE) devices themselves can perform straightforward as self-powered sensors, displaying great application prospects. In this review, the fundamental knowledge of FTE materials and devices are summarized, with recent progresses in the state-of-the-art FTE materials and devices highlighted. The representative sensing application scenarios will be systematically outlined, including temperature sensor, pressure sensor, strain sensor, airflow sensor, respiration sensor, dual-modal sensor, multi-modal senor, and electronic skin are systematically outlined. Finally, the current development bottlenecks, challenges and prospects towards the future development of FTE materials and devices for sensing applications are discussed with a view to drive further advances in the field of self-powered and flexible sensors.