Free Liquid Surface Electrospinning Using a Spiral Tip for Large-Scale Nanofiber Production

Versatile and reliable techniques for generating nanofibers are critical for their large-scale commercial application. This paper proposes a free liquid surface electrospinning method that leverages the unique uniformly distributed spiral projections of linear spiral electrodes for large-scale electrospinning. This technique is instrumental in producing a high curvature of the free liquid surface and the tip effect of the electric field, which efficiently enhances the excitation frequency, quantity, and drafting effect of the jets. The influence of electrode geometry, electrode spacing, and applied voltage on the electric field distribution is simulated using the finite element method. The results show that under the same conditions, the electric field strength of the spiral linear electrode surpasses that of the cylindrical electrode. The interference among the electric field lines disappears with an electrode spacing of 210 mm. Due to the increase in interface curvature, we obtained nanofibers with exceptional morphological characteristics, low dispersion, and adjustable diameters. Simultaneously, the jet density drastically increased, enabling the productivity of nanofibers obtained from a single electrode per unit length to reach 4.27 g/h/m, which is 2-3 orders of magnitude higher than the yield of laboratory electrospinning. Therefore, the electrospinning method that we proposed has the potential to revolutionize the application of nanofibers in large-scale industrial production.