Highly efficient transparent air filter prepared by collecting-electrode-free bipolar electrospinning apparatus

Electrospinning technology has been used for a long time. A jet from a needle was formed by applying high voltage, and then the nanofibers are deposited onto a collecting electrode (usually metal) and the excess charge is conducted away to complete the electrospinning. Alternatively, it is also possible to prevent charge accumulation from hindering the progress of electrospinning by means of charge neutralization. A bipolar electrospinning technique (B-EEM) was developed to induce jets with different charges through a set of high-voltage power supplies of opposite polarity, and the two jets neutralize each other on the insulating mesh, thus completing the electrospinning process. There is no need for a collecting electrode to complete the electrospinning process. We have found that the filters produced by the new technology have better filtration efficiency while maintaining the same transparency in relative to the original technology, and this optimization is due to the distribution modification of the nanofibers on the mesh.