Electrospinning super-assembly of ultrathin fibers from single- to multi-Taylor cone sites

Ultrathin fibers have been widely used in thermal insulation, catalysts, drug delivery, tissue scaffolds, wound dressing, energy storage, energy harvesting, environment engineering, and textile industries. Electrospinning is a facile, universal, and cost-efficient technology for fabricating ultrathin nanofiber materials. On the other hand, porous structure and functional modification can be generated through interfacial assembly method. Accordingly, interfacial electrospinning assembly is emerged as an excellent strategy to prepare multifunctional ultrafine nanofibers. However, the traditional electrospinning using a single Taylor cone is facing a major challenge–low production efficiency, which can no longer meet the actual demand. Therefore, diverse multi-Taylor cone sited electrospinning have been developed, such as multi-needle, various needleless electrospinning and so on. In this review, different electrospinning methods of preparing ultrathin fibers are summarized, especially from the point of view of single Taylor cone site to multi-Taylor cone sites. The precursor materials species, electrospinning apparatus, nanofiber structure and scale-up equipment are critically discussed. It is foreseeable that multi-Taylor cone sited electrospinning can overcome the drawbacks of one Taylor cone sited electrospinning and make the large-scale industrial production possible.