Self-Powered Air Filter Based on an Electrospun Respiratory Triboelectric Nanogenerator

High-efficiency particulate matter (PM) filtration has been an important effort in air purification; however, conventional physical filtration mechanisms are inefficient in blocking submicron particles, which are extremely hazardous to public health. Here, a self-powered triboelectric air filter (STAF) with high efficiency in filtering PM of different sizes is demonstrated. The STAF consists of conductive sponges (CSs) and electrospun fibers (nanofibrils, NFs), which constitute a respiratory triboelectric nanogenerator (R-TENG) through the coupling of the electrical difference between both materials and the respiratory airflow. It utilizes a reciprocating airflow drive to generate triboelectric charges and improve electrostatic adsorption, especially for fine particles. In the experiment, the STAF can maintain a filtration efficiency of 98% for PM2.5 and up to 91.5% for PM0.5, which clearly exceeds the level of commercial masks. In addition, the STAF maintains a high filtration capacity after one month of storage and has a good performance life. This research is of great importance to effectively improve air purification capacity, protect personal health, and prevent respiratory diseases, and it is also of great value to the development of self-driven wearable applications.