The escalating environmental crisis caused by electronic waste demands the use of environmentally friendly, biodegradable natural materials in distributed energy harvesting triboelectric nanogenerators (TENGs) and wearable self-powered devices. Here, we report a fully biodegradable all-cellulose TENG that comprises an electropositive friction layer of carboxymethyl cellulose (CMC) nanofibers doped with lignin nanospheres (LNPs) and an electronegative layer of chemically modified cellulose acetate (DCA) nanofibers. Under repeated contact-separation cycles, the CMC/lignin composite layer generates positive charges while the DCA layer acquires negative charges, yielding an open-circuit voltage of up to 608 V and a short-circuit current of 26 μA, which is the highest output achieved to date among fully degradable TENGs. Enhanced performance arises from charge-induced polarization of the embedded LNPs, thereby increasing the composite dielectric constant and forming distributed nanocapacitors that temporarily retain charge and mitigate surface-charge leakage. In addition, abundant hydroxyl groups in the CMC absorb ambient moisture, promote water-mediated charge transfer and confer excellent humidity resilience. The all-cellulose TENG degrades completely under natural conditions, eliminating electronic-waste concerns. This work advances high-performance, eco-friendly energy harvesters for self-powered sensors and wearable electronics and presents a general strategy based on functional bio-nanosphere inclusion and cellulose chemistry for next-generation biodegradable triboelectric devices. A fully biodegradable all-cellulose TENG integrates lignin nanospheres in CMC nanofibers and DCA counter layers. LNPs induce polarization, forming nanocapacitors that enhance charge retention, achieving 608 V and 26 μA output. Hydroxyl-rich cellulose ensures humidity resilience, enabling eco-friendly, high-performance energy harvesting for wearable and IoT devices. • Cyanoethyl cellulose (CE-cellulose) has universal dual-electric-polarity augmented property. • CE-cellulose based triboelectric nanogenerator (TENG) has ultra-high moisture resistance performance. • The triboelectric charge density (TECD) of this TENG at 95%RH is 533 μC/m 2 , which is a new record.
Zhang et al. (Wed,) studied this question.