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Hierarchical electrospun nanofibers treated by solvent vapor annealing as air filtration mat for high-efficiency PM2.5 capture

通过溶剂蒸汽处理制备多级静电纺丝纳米纤维作为空气过滤膜实现PM2.5高效捕获

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Abstract

Recently, air pollution has become more serious and started to have a dramatic effect on the health of humans in many large cities. Generally, outdoor personal protection, such as commercial masks, cannot effectively prevent the inhalation of many pollutants. Particulate matter (PM) pollutants are a particularly serious threat to human health. Here we introduce a new efficient air filtration mat that can be used for outdoor protection. The new efficient air filter’s nanocomposite materials were successfully fabricated from poly(ε-caprolactone)/polyethylene oxide (PCL/PEO) using an electrospinning technique and solvent vapor annealing (SVA). SVA treatment endows the wrinkled fiber surface and enhances the PM2.5 capture capacity of protective masks. This nanowrinkled air filtration mat can effectively filter PM2.5 with a removal efficiency of 80.01% under seriously polluted conditions (PM2.5 particle concentration above 225 mgm−3). Our field test in Qinhuangdao indicated that the air filtration mat had a high PM2.5 removal efficiency under thick haze. Compared to commercial masks, the fabricated SVA-treated PCL/PEO air filter mat demonstrated a simpler and ecofriendly preparation process with excellent degradation characteristics, showing wide potential applications with a high filtration efficiency.

摘要

空气污染特别是颗粒物(PM)污染, 已经威胁到人类的身体健康, 因而引起了全世界的高度关注. 人们在室外可通过口罩进行个人防 护, 然而一般的商业口罩起不到好的防护效果. 本文利用静电纺丝技术和溶剂蒸汽退火(SVA)方法制备了新型高效的聚(ε-己内酯)/聚环氧 乙烷(PCL/PEO)空气过滤纳米纤维. 通过SVA处理, 纤维表面变得褶皱, 增强了对PM2.5的捕获效率. 在重度污染状况(PM2.5颗粒浓度 >225 mg m−3)下, 这种纳米褶皱空气过滤膜的移除效率达80.01%. 秦皇岛雾霾天实地测量表明, 空气过滤膜能高效移除PM2.5. 与商业口 罩相比, 本文经过SVA处理后的PCL/PEO空气过滤膜具有制备方法简单、环境友好且易降解的特性, 在高效过滤膜领域有潜在应用.

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (21473153 and 51771162), Support Program for the Top Young Talents of Hebei Province, China Postdoctoral Science Foundation (2015M580214), Research Program of the College Science & Technology of Hebei Province (ZD2018091), and the Scientific and Technological Research and Development Program of Qinhuangdao City (201701B004).

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Authors and Affiliations

  1. State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, 066004, China

    Xinxin Huang, Tifeng Jiao & Qiuming Peng

  2. Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, 066004, China

    Xinxin Huang, Tifeng Jiao, Qingqing Liu, Lexin Zhang & Jingxin Zhou

  3. Department of Chemistry, Science of Advanced Materials Doctoral Program, Central Michigan University, Mount Pleasant, MI, 48859, USA

    Bingbing Li

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  1. Xinxin Huang
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Correspondence to Tifeng Jiao or Qiuming Peng.

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Author contributions Huang X, Jiao T, and Peng Q performed and designed the project and experiments. Liu Q, Zhang L, Zhou J, Li B, and Peng Q characterized the materials and discussed the results of the experiments. All the authors commented on the final paper.

Conflict of interest The authors declare no conflicts of interest.

Xinxin Huang is a postgraduate student in Professor Jiao’s group and will receive her master’s degree from the School of Environmental and Chemical Engineering at Yanshan University in 2019. Her current research focus is electrospun nanofiber composite materials for PM2.5 capture applications.

Tifeng Jiao received his PhD degree in physical chemistry from the Institute of Chemistry, Chinese Academy of Sciences (CAS). He was a Postdoctoral Fellow at CNRS (Centre National de la Recherche Scientifique) with Prof. Girard-Egrot (Université Claude Bernard Lyon 1, Lyon, France). Currently, he is a Full Professor and Vice Director of the School of Environmental and Chemical Engineering, Yanshan University. His current research focus includes the synthesis of new self-assembled nanostructured materials and nanocomposites and their related properties.

Qiuming Peng received his BSc degree at Xiangtan University of Technology and his PhD degree in inorganic chemistry from Changchun Institute of Applied Chemistry, CAS. He was an Alexander von Humboldt Fellow with Prof. Karl Ulrich Kainer (GKSS, Germany). In 2011, he was appointed as a Professor at Yanshan University. His current research focus includes high-pressure metallic-based materials and their related mechanical and chemical properties.

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Huang, X., Jiao, T., Liu, Q. et al. Hierarchical electrospun nanofibers treated by solvent vapor annealing as air filtration mat for high-efficiency PM2.5 capture. Sci. China Mater. 62, 423–436 (2019). https://doi.org/10.1007/s40843-018-9320-4

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