Yushan Yang,Hanwei Wang,Chao Wang,Yipeng Chen,Baokang Dang,Ming Liu,Xiaochun Zhang,Yingying Li,Qingfeng Sun
Airborne particulate matter (PM) pollution has caused a public health threat, including nanoscale particles, especially with emerging infectious diseases and indoor and vehicular environmental pollution. However, most existing indoor air filtration units are expensive, energy-intensive, and bulky, and there is an unavoidable trade-off between low-efficiency PM0.3/pathogen interception, PM removal, and air resistance. Herein, we designed and synthesized a two-dimensional continuous cellulose-sheath/net with a unique dual-network corrugated architecture to manufacture high-efficiency air filters and even N95 particulate face mask. Combined with its sheath/net structured pores (size 100–200 nm) consisting of a cellulose framework (1–100 nm diameter), the cellulose sheath/net filter offers high-efficiency air filtration (>99.5338%, Extrafine particles; >99.9999%, PM2.5), low-pressure drops, and a robustness quality factor of >0.14 Pa–1, utilizing their ultralight weight of 30 mg/m2 and physical adhesion and sieving behaviors. Simultaneously, masks prepared with cellulose-sheath/net filters are more likely to capture and block smaller particles than the N95 standard. The synthesis of such materials with their nanoscale features and designed macrostructures may suggest new design criteria for a novel generation of high-efficiency air filter media for different applications such as personal protection products and industrial dust removal.
Xin Tang,Zaixing Zhang,Lingxiao Jing,Kun Luan,Tonghua Zhang,Sha Zhou,Yifan Zhu,Lifan Li,Jiapeng Ye
The outbreak of the 2019 coronavirus pandemic has raised worldwide attention about self-protection from airborne diseases. Air filtration and wearing mask have been proven to be effective measures in reducing the pathogenic aerosol’s transmission. Those lead to an increasing demand of high-efficient filters. However, the nonbiodegradable polymeric materials used in filters can accumulate in landfills or ecosystems, potentially causing pollution after improper disposals. Sustainable and biodegradable alternatives to current filter materials are urgently needed. Yet, very few commercial filters meet these needs. In this paper, a novel quaternary ammonium-halamine compound containing Schiff base and a sandwich-structured preparation strategy were developed. The obtained multifunctional filter consists of a PLA fleece as a support layer, an antimicrobial coating for bactericidal function, and a nanofibrous membrane for the particle removal. The filter demonstrates strong bactericidal properties, killing 97% of Escherichia coli and Staphylococcus aureus at a biocide concentration of only 1 mg/mL. It can rapidly kill bacteria within 5 min contact without leaching antimicrobial substances. Furthermore, it boasts a filtration performance with a success rate over 99.99% and a pressure drop of 45 Pa, which surpasses that of commercial N95 filters for PM0.3. Even under humid conditions, it maintains excellent filtration performance. Our reusability testing result of the developed filters shows that a simple halogenation treatment can renew the halamines and restore the filter’s antimicrobial activity. The filters can degrade in natural soil. The successful development of this sustainable and biodegradable filter material offers a new alternative for high-performance air quality control that protect public health.
危险品化学品经营许可证（带存储）