Coaxial Free Surface Electrospinning

Disclosed are methods that utilize the differences in physical properties between two coating fluids to form core-shell particles or core-shell fibers by coaxial free-surface electrospinning. The methods are able to achieve higher productivity than known methods, and are tunable. Nonwoven fiber mats of electrospun fibers have garnered much scientific and commercial interest in recent years due to their unique properties, such as their high porosity, high surface area and small diameter fibers.