Washable Multilayer Triboelectric Air Filter for Efficient Particulate Matter PM_2.5 Removal

Abstract

Efficient removal of particulate matter (PM) is the major goal for various air cleaning technologies due to its huge impact on human health. Here, a washable high-efficiency triboelectric air filter (TAF) that can be used multiple times is presented. The TAF consists of five layers of the polytetrafluoroethylene (PTFE) and nylon fabrics. Compared with traditional electrostatic precipitator, which requires a high-voltage power supply, the TAF can be charged by simply rubbing the PTFE and nylon fabrics against each other. The electrical properties of the TAF are evaluated through the periodic contacting-separating of the PTFE and nylon fabrics using a linear motor, and an open-circuit voltage of 190 V is achieved. After charging, the TAF has a removal efficiency of 84.7% for PM 0.5 , 96.0% for PM 2.5 , which are 3.22 and 1.39 times as large as the uncharged one. Most importantly, after washing several times, the removal efficiency of the TAF maintains almost the same, while the commercial face mask drops to 70% of its original efficiency. Furthermore, the removal efficiency of the PM 2.5 is very stable under high relative humidity. Therefore, the TAF is promising for fabricating a reusable and high-efficiency face mask.

Triboelectric Nanogenerator: A Foundation of the Energy for the New Era

“…Application of TENG as direct HV power sources. [22] Copyright 2018, Wiley-VCH. Reproduced with permission.…”

“…[21] Charged particles were then collected by the electrodes due to Coulombic forces of attraction and repulsion. [22] The TAF could be charged by simply rubbing the fabrics against each other and achieved a removal efficiency of 84.7 and 96.0% for PM 0.5 and PM 2.5 , respectively. [137] Moreover, a self-powered triboelectric filter consisting of vibratory PTFE pellets and electrode plates was developed to remove the PM in automobile exhaust fumes using the self-vibration of the tailpipe, achieving a mass collection efficiency of ≈95.5% for PM 2.5 ( Figure 15b).…”

A Fluffy Dual‐Network Structured Nanofiber/Net Filter Enables High‐Efficiency Air Filtration

“…However, due to the inherent limit on their micro‐sized diameters (usually >5 µm), traditional fibrous filters, for instance, melt‐blown microfibers and glass microfibers still suffer from fatal structure defect of large pore size when they have low thickness. Therefore, microfiber filters have to be stacked thick (usually several millimeters) to achieve effective PM removal, which resulted in serious deterioration of air permeability . Moreover, these filters are almost inefficient for PM 0.3 (particles with the most penetrating size of 0.3 µm) filtration, and remain defects of high material consumption (>70 g m −2 ), high energy consumption, and limited light transmittance …”

Controlling Surface Charge Generated by Contact Electrification: Strategies and Applications

“…In terms of the environment, the removal of the particulate matter (PM) from the exhaust fumes of automobile is highly desirable in urban areas. Devices for the filtration of gas based on contact electrification have been developed . One self‐powered device consisted of multiple PTFE pellets (2 mm in diameter) in a gas channel sandwiched between a top and a bottom electrode (Figure j); vibration of the engine of the automobile allowed the pellets to move and charge against the electrodes.…”