Triboelectric Nanogenerator\nMade with Stretchable,\nAntibacterial Hydrogel Electrodes for Biomechanical Sensing

Triboelectric nanogenerators (TENGs) have attracted widespread\nattention as a promising candidate for energy harvesting due to their\nflexibility and high power density. To meet diverse application scenarios,\na highly stretchable (349%), conductive (1.87 S m<sup>–1</sup>), and antibacterial electrode composed of carbon quantum dots/LiCl/agar-polyacrylamide\n(CQDs/LiCl/agar-PAAm) dual-network (DN) hydrogel is developed for\nwearable TENGs. Notably, the concentration of agar alters the pore\nspacing and pore size of the DN hydrogel, thereby impacting the network\ncross-linking density and the migration of conductive ions (Li<sup>+</sup> and Cl<sup>–</sup>). This variation further affects\nthe mechanical strength and conductivity of the hydrogel electrode,\nthus modulating the mechanical stability and electrical output performance\nof the TENGs. With the optimal agar content, the tensile strength\nand conductivity of the hydrogel electrode increase by 211 and 719%,\nrespectively. This enhancement ensures the stable output of TENGs\nduring continuous operation (6000 cycles), with open-circuit voltage,\nshort-circuit current, and transferred charge increasing by 200, 530,\nand 155%, respectively. Additionally, doping with CQDs enables the\nhydrogel electrode to effectively inhibit the Gram-negative bacterium Escherichia coli. Finally, the TENGs are utilized\nas a self-power smart ring for efficient and concise information transmission\nvia Morse code. Consequently, this study introduces a creative approach\nfor designing and implementing multifunctional, flexible wearable\ndevices.