Spider‐Web‐Inspired PM_0.3 Filters Based on Self‐Sustained Electrostatic Nanostructured Networks

Abstract

Particulate matter (PM) pollution has become a serious public health issue, especially with outbreaks of emerging infectious diseases. However, most present filters are bulky, opaque, and show low‐efficiency PM0.3/pathogen interception and inevitable trade‐off between PM removal and air permeability. Here, a unique electrospraying–netting technique is used to create spider‐web‐inspired network generator (SWING) air filters. Manipulation of the dynamic of the Taylor cone and phase separation of its ejected droplets enable the generation of 2D self‐charging nanostructured networks on a large scale. The resultant SWING filters show exceptional long‐range electrostatic property driven by aeolian vibration, enabling self‐sustained PM adhesion. Combined with their Steiner‐tree‐structured pores (size 200–300 nm) consisting of nanowires (diameter 12 nm), the SWING filters exhibit high efficiency (>99.995% PM0.3 removal), low air resistance (<0.09% atmosphere pressure), high transparency (>82%), and remarkable bioprotective activity for biohazard pathogens. This work may shed light on designing new fibrous materials for environmental and energy applications.

Electrospun ultrafine fibers for advanced face masks

“…The filters enabled the high-efficiency (≈99.998%) capture of PM 0.3 with super lightweight while maintaining low air resistance (≈0.1% atmosphere pressure), and showed integrated properties of superhydrophobicity and desirable transparency (91%). Similarly, Zhang et al created spider-web-inspired PM 0.3 filters based on self-sustained electrostatic nanostructured networks using a unique electrospraying-netting technique [ 109 ]. The spider-web-inspired network generator (SWING) filters showed the exceptional long-range electrostatic property and exhibited high efficiency (>99.995% PM 0.3 removal), low air resistance (<0.09% atmosphere pressure) and high transparency (>82%) in combination with their steiner-tree-structured pores (size 200−300 nm) consisting of nanowires (diameter 12 nm).…”

Development of Electrospun Nanofibrous Filters for Controlling Coronavirus Aerosols

“…More evidences have highlighted the importance of the airborne transmission of SARS-CoV-2, the causative agent of COVID-19. 12 Aerosols (< 5 μm) can suspend in the air for a long duration, accumulate in a closed environment, remain infectious (the half-life of SARS-CoV-2 in aerosols is 1.1 h), 3 and thus involve in the long-range transmission of airborne diseases. Therefore, there is an urgent need to control the airborne transmission of SARS-CoV-2.…”

“…The large porosity of electrospun air filters can also reduce air pressure drop in filtration as well as enhance the breathability of masks/respirators. 12 More importantly, electrospinning is operated under a strong electric field (i.e., 1-5 kV cm -1 ), and it produces filters with retained surface and volume charges that can last for weeks or even months. The presence of the retained charges can significantly promote aerosol capture through electrostatic attraction.…”

Design of Polypropylene Electret Melt Blown Nonwovens with Superior Filtration Efficiency Stability through Thermally Stimulated Charging

“…The current preventive approaches include wearing personal protective masks, such as N95 respirators. In addition to the disease, fine particulate matter (PM) pollution has drawn worldwide attention due to its serious threat to public health, daily lives, visibility, climate, and ecosystems [ 2 , 3 , 4 ]. Electret filters are widely used in PM filtration and virus defense due to their cost-effectiveness, energy-saving features, high filtration efficiency, and low pressure drop [ 5 ].…”