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

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  • ReceivedMay 28, 2018
  • AcceptedJul 2, 2018
  • PublishedAug 8, 2018


Funded by

the National Natural Science Foundation of China(21473153,51771162)

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)


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).

Interest statement

The authors declare no conflicts of interest.

Contributions statement

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.

Author information

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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  • Figure 1

    A schematic illustration of the preparation and filtration of the obtained electrospun nanowrinkled air filtration mat.

  • Figure 2

    (a) SEM images and fiber diameter size distributions of the prepared PCL/PEO nanofibers mat (Sample 1) by electrospinning (a and a') and subsequent by SVA treatment for 5 day (b and b').

  • Figure 3

    SEM images of the prepared electrospun PCL/PEO nanofibers (a, Sample 1) and SVA treatment at different time intervals: (b), one day; (c), 2 days; (d), 3 days; (e), 4 days; (f), 5 days.

  • Figure 4

    XRD patterns of the prepared PCL/PEO nanofibers (a) and with different subsequent SVA treatment time intervals (b).

  • Figure 5

    TG curves and infrared spectra of the PCL/PEO nanofiber mat by electrospinning and subsequent SVA treatment time of 5 days.

  • Figure 6

    Schematics of the air filtration mat that captured PM2.5 by air flow (a) and working state with mask filtration (b); (c) PM2.5 filtration curves for the air filtration mat (Sample 1) with different volumes of spinning precursor solution; (d) PM2.5 removal efficiency plots for primary fibers and SVA-treated fibers.

  • Figure 7

    SEM images and fiber diameter size distributions of the prepared PCL/PEO nanofiber mat by electrospinning (Sample 2, a and a'; Sample 3, c and c') and subsequently with SVA treatment at a time of 5 days (Sample 2, b and b'; Sample 3, d and d').

  • Figure 8

    (a) Comparison chart of PM2.5 removal efficiency of Sample 2 and Sample 3 with/without SVA treated fibers. (b) Comparison chart of PM2.5 removal efficiency of Sample 3 deposited on different commercial masks.

  • Figure 9

    (a) Photo of a commercial mask covered with an electrospun mat (Sample 1) after air filtration; (b, c) TEM and SEM characterization of the morphologies of Sample 1 attached to PM2.5 particles; (d) EDX composition analysis of PM2.5 particles.

  • Figure 10

    C 1s and O 1s deconvolutions in the XPS profiles of electrospun mat (Sample 1) before (a, b) and after (c, d) air filtration.

  • Table 1   Comparative characteristics and filtration performance of different materials reported in the literatures



    Fiber diameter


    Filter media








    Incense smoke

    Transparent, environmentally high stability and highly effective removal of PM2.5

    Low reusability, easy to aging, low strength, poor wear resistance



    Polylactic acid





    Controllable morphology, excellent filtration efficiency and a low pressure drop

    Poor stability, poor wear resistance and easy to aging



    Nylon6 (PA-6)




    Good stability, good air permeability and good PM2.5 remove

    Easy to aging and low intensity








    Excellent elasticity, good abrasion resistance and good PM2.5 remove

    Poor stability and easy to aging






    NaCl aerosol

    High porosity, high filtration efficiency and good stability.

    Poor air permeability, poor cycle performance



    Polyvinyl chloride /polyurethane





    Good tensile strength, high abrasion resistance and high filtration efficiency

    Poor cycle performance and easy to aging



    Polyacrylonitrile /polyurethane (PAN/PU)




    Superhydrophobicity, controllable morphology, porous structure

    Poor air permeability, poor cycle performance



    Polyacrylonitrile /silica nanoparticles (PAN/SiO2)




    Layer-by-layer assisted stacking structure and high filtration efficiency

    Stability is poor, low strength, poor wear resistance



    Present work



    Adjustable nanostructure, high strength, high stability and high toughness

    Sensitive to temperature and solvents