Recent Progress in Textile-Based Triboelectric Force Sensors for Wearable Electronics

Force sensors based on triboelectric nanogenerator (TENG) technology show promising applications in wearable electronics due to the significant advantages in biomechanical energy harvesting and self-powered sensing capabilities. Meanwhile, textiles are considered the ideal design platform for wearable electronics owing to the superiorities in breathability, wearability, as well as large-area availability. Integrating TENG technology with modern textile processes, the textile-based triboelectric force sensors (tTEFSs) have procured immense interest in the past decade. In the current review, we provide an overview of the state-of-the-art progress in tTEFSs with various working modes, including vertical contact-separation mode, single electrode mode, lateral sliding mode, and freestanding mode. Based on structural characteristics and fabrication techniques, the tTEFSs can be divided into three categories, including one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) tTEFSs. For each category, recent progress in the structural designs, preparation methods, working principles, and applications are systematically summarized. In addition, we also comprehensively introduce strategies adopted in recent years to further enhance output performance of tTEFSs, including surface chemical modification, designing physical microstructure, enhancing dielectric properties, and combined method. The effect of each enhancement strategy is discussed to provide researchers with guidance for designing tTEFSs with excellent output performance. Finally, the potential difficulties and current challenges that hinder the practical applications of tTEFSs are discussed.