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The rapid development of wearable electronics has placed higher demands on the design strategies of triboelectric materials. Aerogels have the potential to become advanced triboelectric materials, however, traditional design strategies often require complex processes and additional chemical cross‐linking agents to improve the stability of the gel structure, which limits its practical application. In this work, a scalable and sustainable self‐assembly drive strategy is proposed for the design of bio‐based triboelectric aerogels with multi‐scale winding structures. Interestingly, the autoacceleration effect, which is regarded as "unfavorable" during the autocatalytic polymerization of supramolecules, is rationally exploited to provide the supramolecules within the matrix with an abundance of multiple hydrogen bonds at the same time as their rapid gelation occurs. Thanks to this, the aerogel film exhibits ultra‐high tensile strength (104 MPa) and remains undeformed after resisting an impact of 8000 times its own weight. Highly robust triboelectric aerogel films are used to build wearable self‐powered sensors with ultra‐fast response in complex environments (48 ms), while enabling real‐time interaction between the wearer and the information network. The design idea of " turning a detriment into an asset " in this work provides a new idea for the material construction of highly robust wearable sensors. [ABSTRACT FROM AUTHOR]

Highlights: Typical structures/working mechanisms of gel-based triboelectric nanogenerators and performance advantages of gel materials reviewed. Optimization of hydrogels, organogels, and aerogels for triboelectric nanogenerators in flexible sensing summarized. Applications, challenges, and future development directions of gel-based triboelectric nanogenerators in flexible sensing are discussed. The rapid development of the Internet of Things and artificial intelligence technologies has increased the need for wearable, portable, and self-powered flexible sensing devices. Triboelectric nanogenerators (TENGs) based on gel materials (with excellent conductivity, mechanical tunability, environmental adaptability, and biocompatibility) are considered an advanced approach for developing a new generation of flexible sensors. This review comprehensively summarizes the recent advances in gel-based TENGs for flexible sensors, covering their principles, properties, and applications. Based on the development requirements for flexible sensors, the working mechanism of gel-based TENGs and the characteristic advantages of gels are introduced. Design strategies for the performance optimization of hydrogel-, organogel-, and aerogel-based TENGs are systematically summarized. In addition, the applications of gel-based TENGs in human motion sensing, tactile sensing, health monitoring, environmental monitoring, human–machine interaction, and other related fields are summarized. Finally, the challenges of gel-based TENGs for flexible sensing are discussed, and feasible strategies are proposed to guide future research. [ABSTRACT FROM AUTHOR]

Material designs for wearable sensors are increasingly important due to variable application scenarios and environmental disturbances. The high temperatures pose a significant challenge to the performance of sensing materials. The reasonable anisotropic structure in materials is recognized as a promising approach to address this challenge. Precise control of the orientation of the material remains difficult, owing to the entropy effect. In this work, a tunable anisotropic triboelectric aerogel via an in situ coupled magnetic alignment and protonation reduction strategy is demonstrated. The designed orientation with a fitting degree of 98% can effectively suppress electron thermionic emission, which enables the surface charge density to reach 75 µC m−2 at 300 °C. Such a perfect coordination between self‐powered sensing and thermostability innovates multifunctional wearable sensing design at high temperatures, allowing aramid‐based aerogel to be a candidate for advanced sensing materials for applications in the military and aerospace fields. [ABSTRACT FROM AUTHOR]

The advent of self‐powered wearable electronics will revolutionize the fields of smart healthcare and sports monitoring. This technological advancement necessitates more stringent design requirements for triboelectric materials. The triboelectric aerogels must enhance their mechanical properties to address the issue of structural collapse in real‐world applications. This study fabricates stiff nanocellulosic triboelectric aerogels with multiscale structures induced by the Hofmeister effect. The aggregation and crystallization of polymer molecular chains are enhanced by the Hofmeister effect, while ice crystal growth imparts a porous structure to the aerogel at the micron scale. Therefore, the triboelectric aerogel exhibits exceptional stiffness, boasting a Young's modulus of up to 142.9 MPa and a specific modulus of up to 340.6 kN m kg–1, while remaining undeformed even after supporting 6600 times its weight. Even after withstanding an impact of 343 kPa, highly robust wearable self‐powered sensors fabricated with triboelectric aerogels remain operational. Additionally, the self‐powered sensor is capable of accurately detecting human movements, particularly in abnormal fall postures detection. This study provides considerable research and practical value for promoting material design and broadening application scenarios for self‐powered wearable electronics. [ABSTRACT FROM AUTHOR]