Recent advances in triboelectric nanogenerator-based self-powered sensors for monitoring human body signals

Recently, there is a growing emphasis on the utilization of wearable devices for monitoring various aspects of human body movement. However, a persistent obstacle in the way of their widespread adoption is the requirement for an external power to keep them operational. Triboelectric nanogenerator (TENG), an emerging power technology, can convert low-frequency mechanical energy into real-time electrical signals and obtain corresponding mechanical motion characteristics, enabling self-powered human body signal monitoring with advantages of compact size, easy preparation, and low cost. It offers a promising avenue for advancing the field of human motion monitoring without an external power. In this review, we systematically review the latest progress of TENG-based human body signals sensors (HBSSs) in terms of working mechanism, design principles, function integrations and monitoring accuracy, as well as the corresponding TENG based wearable device advantages in sensitivity, stability and wearing comfort. According to the monitoring field, TENG-based HBSSs can be divided into two kinds of researching directions, which contain the basic physiological signals monitoring and motion signals monitoring. Some representative applications in these two aspects are summarized to highlight the superiorities of TENG-based HBSSs. Further, the current challenges and promising solutions for future TENG-based HBSS are outlined, including sensitivity, stability, and wearing comfort, which will better steer new researchers toward a deeper understanding and exploration of TENG for the self-powered sensing technology.