Fiber composites-based flexible triboelectric nanogenerators: from material design to emerging applications

The rise of portable electronic devices and Internet of Things (IoT) has spurred significant interest in flexible triboelectric nanogenerators (TENGs) as sustainable energy solutions. The electrical performance of TENGs is profoundly influenced by nanoscale factors, including interface properties and material characteristics, highlighting the critical need for a comprehensive understanding of these parameters to unlock their full potential. This paper summarizes the recent advances in advanced fiber composite TENGs (FC-TENGs), especially electrospun nanofibers, with a focus on key nanoscale properties, covering triboelectric layer interface characteristics, dielectric constant, electron affinity, and crystal phase, all of which are fundamental to optimizing their output performance. Additionally, it explores emerging applications of FC-TENGs in wearable electronics, self-powered sensors, wireless communication systems, human-machine interfaces, and modern healthcare technologies. The review concludes by addressing existing challenges, evaluating future opportunities, and outlining research directions for advancing FC-TENGs. By bridging foundational material science with innovative applications, this review seeks to inspire the development of high-performance, self-powered electrospun composite tribovoltaic nanogenerators, paving the way for a wireless, artificial intelligence (AI)-enabled IoT era.