RGO-functionalized polymer nanofibrous membrane with exceptional surface activity and ultra-low airflow resistance for PM2.5 filtration

A polar polymer nanofibrous membrane (NFM) made by electrospinning is capable of capturing particulate matter (PM) on the junctions of cross-linked nanofibers through dipole-dipole intermolecular forces. However, the realization of fast and high-efficiency PM2.5 filtration under a high gas-velocity condition is still a big challenge for the pure polymer NFM. Herein, we introduce reduced graphene oxide (rGO) nanosheets (NSs) into the electrospun polyacrylonitrile (PAN) NFM to enhance both the surface activity and the gas permeability of the composite NFM during air filtration. By combining the experimental results with the theoretical calculations, we demonstrate that the rGO NSs dispersed on/in the PAN NFM remarkably increase the PM2.5 capture sites on the uncross-linked nanofibers based on both hydrogen bonding and dipole-dipole interaction forces. Furthermore, the tensile strength of the rGO-functionalized PAN NFM (0.48-1.25 MPa) is much higher than that of the pure PAN NFM (0.19 MPa) due to the excellent mechanical properties of the rGO NSs. The enhanced tensile strength of the composite NFM effectively boosts the gas permeability during air filtration. In this way, the optimal NFM containing 2.5 wt% rGO NSs exhibited >99.9% PM2.5 removal efficiency, approximate to 0.094 Pa-1 quality factor, and only approximate to 70 Pa pressure drop for resisting the airflow with a high gas velocity of approximate to 20 L min(-1).

通过电纺丝制备的极性聚合物纳米纤维膜（NFM）能够通过偶极-偶极分子间力捕获交联纳米纤维交界处的颗粒物质（PM）。然而，在高气体流速条件下实现快速高效的PM2.5过滤对于纯聚合物NFM仍然是一个巨大的挑战。在本文中，我们将还原的氧化石墨烯（rGO）纳米片（NSs）引入到电纺聚丙烯腈（PAN）NFM中，以增强空气过滤过程中复合NFM的表面活性和透气性。通过将实验结果与理论计算相结合，我们证明基于氢键和偶极-偶极相互作用力，分散在PAN NFM上/中的rGO NSs显着增加了未交联纳米纤维上的PM2.5捕获位点。此外，由于rGO NSs的优异机械性能，rGO官能化PAN NFM（0.48-1.25 MPa）的拉伸强度比纯PAN NFM（0.19 MPa）高得多。复合NFM的增强抗张强度有效地提高了空气过滤过程中的透气性。这样，包含2.5 wt％rGO NS的最佳NFM表现出> 99.9％的PM2.5去除效率，大约为0.094 Pa-1的品质因数，并且仅大约70 Pa的压降可抵抗高气流速度的气流。约20 L min（-1）。

Published:2018

Journal ：Environmental Science-Nano

Impact Factor：There is no data at this time

Paperlink: https://pubs.rsc.org/--/content/articlelanding/2018/en/c8en00468d/unauth#!divAbstract