A high-performance triboelectric nanogenerator with improved output stability by construction of biomimetic superhydrophobic nanoporous fibers

The utilization of nanoporous materials is an extremely effective approach to enhance the electrical performance of triboelectric nanogenerators (TENGs). However, existing methods for preparing nanoporous tribo-materials are not only complicated, costly and time-consuming, but also waste a lot of material. Meanwhile, fabricated nanoporous tribo-materials that have low roughness by nature possess poor surface hydrophobicity, causing low output stability in humid environments. Here, a bio-inspired petiole-like micron fiber-based tribo-material with inner nanopores, rough surface nanostructures and superhydrophobicity is first designed that uses an extraordinarily simple, ultralow-waste and efficient single-component electrospinning process. The petiole-like structures and superhydrophobicity endow the assembled triboelectric nanogenerator (PMF-TENG) with outstanding electrical performance and superior output stability under humid conditions. With a giant power density of 56.9 W m-2 and a high peak-to-peak output voltage of 2209 V, the optimized PMF-TENG can not only be used as a biomechanical energy harvester to directly drive 833 light-emitting-diodes and small electronics, but also serve as a self-powered sensor to detect body motions. Moreover, under a high relative humidity of 80%, the output retention rate of the optimized PMF-TENG is 1.7 and 2.2 times higher than the TENG assembled with the traditional smoother solid nanofiber-based tribo-material and the monolithic nanoporous tribo-material-based TENG, respectively. This work provides an easy-to-fabricate high-performance nanoporous material-based TENG with ultralow material waste and extends its potential for application in humid conditions.