Printing Bioderived and Biodegradable Triboelectric Nanogenerators via Dual-Head Additive Manufacturing

Society needs regenerative technology, that is, technology that replenishes the world as it functions. While energy harvesting technology, including triboelectric nanogenerators (TENGs), provide promise to contribute to replacing polluting fossil fuels, these devices are often produced from petrochemically derived polymers and require energy-intensive processing steps during formation, limiting their true green energy function. Here, we describe an approach to produce TENGs via dual-head 3D printing of two plant-based inks of functionalized rapeseed oil and soybean oil and isobornyl acrylate (typically derived from turpentine oil). Using these plant-based formulations, two mechanically different materials, required for TENGs, were created and printed in both film and 3D morphologies. The simplified design eliminates the integration of internal electrodes in a 3D structure, and the 3D-printed TENG structures show an electromechanical response an order of magnitude higher than that of structures from single polymers. This study paves the way toward more responsive 3D TENG architectures for improved mechanical energy harvesting.