A bladeless wind-tunnel generator based on a flutter-driven triboelectric nanogenerator with on-demand micro-structuring

With the unremitting demand for renewable energy sources, triboelectric nanogenerators as efficient micro-energy, particularly wind-energy harvesting devices, have garnered increased attention. This study introduces an innovative wind flutter-driven triboelectric nanogenerator (WF-TENG). It employs an on-demand integrated design of a "mortise and tenon" microstructure and is assembled in a "negative-positive-negative" configuration mimicking a "corrugated paper" macrostructure, effectively converting wind energy into electrical energy. The porous crosslinked ethyl cellulose/polyethyleneimine positive friction layer and the bionic rose-petal-like fluorinated ethylene propylene negative friction layer are assembled to form a miniaturized "mortise and tenon" structure, which greatly improves the charge transfer efficiency. Surprisingly, due to the collaborative structural design on micro-/macro-scale, WF-TENG elevates the breakthrough power density of WF-TENG to 455.932 mW cm−2. Further, the integrated-equipped bladeless wind tunnel generator, assembled with the WF-TENG array, utilizes airflow disturbances to produce high-frequency flutter-driven frictional motions. This system outputs up to 7.5 kV at a startup wind speed of 7.9 m s−1 and maintains stable performance for 60 days. Application experiment substantiates the ample electrical energy collected by the bladeless wind tunnel generator for powering an indoor formaldehyde purifier demonstrates a high formaldehyde purification rate of 94 %, providing new insights for the design and applications of novel micro-energy harvesting devices.