Moisture and oily molecules stable nanofibrous electret membranes for effectively capturing PM2.5
Moisture and oily molecules stable nanofibrous electret membranes for effectively capturing PM2.5
复制标题
水分和油性分子稳定的纳米纤维驻极体膜，可有效捕获 PM2.5
DOI：
10.1016/j.coco.2017.08.004
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发表时间：
2017-12-01
影响因子：
8
通讯作者：
Ding, Bin
中科院分区：
文献类型：
--
作者：
Jiang, Pan;Zhao, Xinglei;Ding, Bin
由于严重的雾霾污染，具有高相对湿度（80-90%）和含油成分（30-40%）的特点，制造对水分和油性分子具有强大电荷稳定性的驻极体空气过滤器变得越来越重要；然而，这仍然是一个持续的挑战。本文通过静电纺丝技术，成功设计了一种纳米纤维驻极体膜，该膜能够在含有水分和油性成分的环境中高效、低空气阻力地持久捕获PM2.5。受益于聚乙烯醇丁醛（PVB）的高电阻率和氮化硅纳米颗粒（Si3N4 NPs）的高介电常数，当电荷增强剂（Si3N4）的含量从0 wt%增加到1 wt%时，PVB/Si3N4纳米纤维膜的稳定表面电位从1610提高到2010 V。更重要的是，揭示了水和油条件下的电荷耗散机制。此外，通过进一步引入疏水疏油氟化聚氨酯（FPU），与PVB/Si3N4膜相比，PVB/Si3N4膜在高相对湿度（85%）下的稳定表面电位提高了62.8%，在含油组分下的稳定表面电位提高了48.4%。所得膜具有99.950%的高过滤效率，55.0 Pa的低空气阻力，耐用性强，为雾霾环境中驻极体空气过滤材料的设计提供了指导。
The fabrication of electret air filter with robust charge stability towards moisture and oily molecules is becoming increasingly essential due to the severe haze pollution, which is featured with high relative humidity (80-90%) and contains oily components (30-40%); however, this remains an ongoing challenge. Herein, a nanofibrous electret membrane able to enduringly capture PM2.5 with high efficiency and low air resistance under the surroundings containing moisture and oily components is successfully designed via electrospinning. Benefiting from the high electrical resistivity of polyvinyl butyral (PVB) and high dielectric constant of silicon nitride nanoparticles (Si3N4 NPs), PVB/Si3N4 nanofibrous membranes are endowed with improved stable surface potentials from 1610 to 2010 V when the content of charge enhancer (Si3N4) increases from 0 to 1 wt%. More importantly, the charge dissipating mechanism under water and oil condition is revealed. Moreover, by further introducing hydro-oleophobic fluorinated polyurethane (FPU), the stable surface potentials of PVB/Si3N4-FPU membranes are elevated by 62.8% under high relative humidity (85%) and 48.4% towards oily components, compared with PVB/Si3N4 membranes. The resultant membranes achieve a high filtration efficiency of 99.950%, low air resistance of 55.0 Pa, and robust durability, providing a guidance for the design of electret air filtration materials used in haze environment.