Airborne particulate matter (PM) pollution has raised serious concerns over both the global climate and public health. Therefore, there is an urgent need for air filters of high-efficiency and energy-saving. Pore structure optimization and electret enhancement are feasible means to improve their filtration performance. Herein, a novel sandwich-structured electret composite filter with a low pressure drop and robust filtration stability was successfully designed and fabricated. The composite filter was composed of fluffy PS microfibers with large electric resistivity and high porosity, and PAN nanofibers with high polarity and small pore size. Benefiting from the fluffy structure constructed by electrospinning at the right humidity, the tortuous pore channels created by the appropriate mixing of microfibers and nanofibers, and the abundant static charges generated by the hybrid of polar and nonpolar polymer materials, the PS/PAN/PS composite filter possessed a high filtration efficiency of 99.96% for particles of 0.30 μm, a low pressure drop of 54 Pa and a satisfactory quality factor value of 0.1449 Pa-1 at an airflow velocity of 5.3 cm/s. In particular, the composite filter exhibited better electret stability and PM2.5 loading performance than the commercial ones, which guarantees its long-term storage and usage.

中文翻译：

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稳定的微米/纳米复合驻极体滤波器的制造和性能，可有效捕获PM2.5。

空气中的颗粒物（PM）污染已引起对全球气候和公共卫生的严重关注。因此，迫切需要一种高效节能的空气过滤器。孔结构优化和驻极体增强是提高其过滤性能的可行手段。在这里，成功地设计和制造了具有低压降和鲁棒的过滤稳定性的新型夹心结构驻极体复合过滤器。该复合过滤器由具有高电阻率和高孔隙率的蓬松PS微纤维和具有高极性和小孔径的PAN纳米纤维组成。得益于在适当的湿度下静电纺丝形成的蓬松结构，通过适当混合微纤维和纳米纤维而形成的曲折孔道，以及极性和非极性聚合物材料混合产生的大量静电荷，PS / PAN / PS复合过滤器对0.30μm的颗粒具有99.96％的高过滤效率，54 Pa的低压降和令人满意的品质因数气流速度为5.3 cm / s时，其值为0.1449 Pa-1。尤其是，复合滤波器比商用滤波器具有更好的驻极体稳定性和PM2.5负载性能，从而保证了其长期存储和使用。