Touch-activated information interaction system based on body-heat-powered flexible thermoelectric generator for food spoilage monitoring

With the rapid advancement of the Internet of Things, a wide range of information interaction platforms have been developed to enhance the quality of life and work. Nevertheless, rigid batteries greatly limit its development, which requires frequent replacement or recharge. Thermoelectric generators (TEG) have emerged as an attractive form for energy suppliers owing to their ability to convert low-grade energy heat into sustainable electricity. Herein, we have implemented a flexible TEG-based multifunctional information interaction system, which utilizes body heat to enable information interaction through finger touch. To increase the efficiency of energy conversion, the flexible TEG achieves high performance by optimizing the filling factor and material thermal conductivity, leading to a normalized power density of 1.43 μW/cm2 K2. As a proof-of-concept demonstration, the system has been applied to food spoilage monitoring with an MXene-based sensor to achieve stable and sensitive ammonia detection. The TEG-based information interaction system provides an attractive solution for intelligent packaging and will act as an exciting platform for human body energy harvesting and human–machine interaction for point of care testing.