Natural lignocellulosic nanofibrils as tribonegative materials for self-powered wireless electronics.

Triboelectric nanogenerators (TENGs) are promising energy harvesting devices for powering next generation wearable electronics. TENGs performance are largely determined by the triboelectric effect between the tribonegative and tribopositive layers. To date, fluorine-containing petroleum-based polymers, such as polytetrafluoroethylene (PTFE), remain the most popular choice as tribonegative layer due to their high tribonegativity against various materials during frictional contact. We report for the first time a natural wood-derived lignocellulosic nanofibrils (LCNF) tribolayer that could replace fluorine-containing petroleum-based polymers as a tribonegative material for TENGs. The high tribonegativity was due to the presence of natural lignin on the surface of LCNF and LCNF's nanofibril morphology. The LCNF nanopaper-based TENGs produced significantly higher voltage (~160%) and current (~120%) than TENGs with PTFE as the tribonegative material when paired with various polymeric/metallic tribolayers. Furthermore, assembling LCNF nanopaper as the tribonegative layers into a cascade TENG generated an output sufficient for powering a wireless communication node, capable of sending a radio-frequency signal to a smartphone every 3 min. This study demonstrates the excellent promises of using LCNF to make high-performance and more environmentally friendly wireless self-powered electronics; and thus pinpoints a new approach for fabricating sustainable triboelectric nanogenerators using natural lignocellulosic materials instead of conventional fluorine-containing petroleum-based polymers as tribonegative layers. [Display omitted] • We explore the effect of natural lignin bound on the cellulosic nanofibrils on the triboelectric properties of the nanopapers. • We introduce the first natural material as a superior alternative to tribonegative fluorine polymers for TENGs. • A cascade LCNF nanopaper-based TENGs was capable of powering energy-intensive wireless communication nodes. • LCNF energy-harvesting capability and reliability toward sustainable self-powered IoT devices was demonstrated. [ABSTRACT FROM AUTHOR]