Microspace Triboelectric Nanogenerator Based on Biocompatible Lignin-Derived Activated Carbon for Advanced Active Sensing Applications

Triboelectric nanogenerators (TENGs) offer inherent advantages, such as self-powering capability, high sensitivity, and structural adaptability. These qualities make them promising candidates for applications, including the Internet of Things (IoT) and active sensors. The sensitivity of conventional TENG-based sensors is highly affected by environmental factors due to the direct exposure of the triboelectric active regions to ambient conditions. Hence, this paper proposes a strategy to integrate a microspace triboelectric nanogenerator (MS-TENG), using biobased lignin-derived activated carbon (LDAC) as a tribopositive electrode that can reduce the environmental exposure of tribo-layers for advanced active sensor applications. The MS-TENG exhibits highly sensitive behavior due to the excellent physicochemical properties, such as high surface area, porous morphology, several oxygenated surface functional groups, and conductivity. Furthermore, the MS-TENG array structure is assembled for real-time voltage acquisition, enabling the precise detection of slight body movements. Especially, the fabricated MS-TENG-based active sensor demonstrates outstanding performance by successfully distinguishing motion data (e.g., fingers and wrist motions) in the metaverse, underscoring its potential as a highly reliable sensing device. More importantly, in a low-pressure regime (<4 N), the proposed MS-TENG device presents a 2-fold increase in sensitivity (slope ∼ 12.1 V/N) as compared to conventional TENG (slope ∼ 5.62 V/N) owing to increased reaction force. This work opens opportunities for TENGs, positioning them as promising candidates for active sensing and soft wearable applications.