Instantaneous self-assembly of three-dimensional silica fibers in electrospinning: Insights into fiber deposition behavior

Producing three-dimensional (3D) fibers in electrospinning has been a challenge and has greatly limited the application of electrospun fibers in 3D. In this study, we propose a new method of fabricating 3D silica fiber stacks through self-assembly electrospinning. Three-dimensional fibers were instantly collected as the spinning started by simply placing conductive tips on the flat collector, without the addition of a additives or extra environmental controls. The 3D fiber deposition and growth behavior was studied specifically to reveal the underlying mechanism. It was found that electrostatic repulsion among fibers caused a loose pack of fibers, and the rapid solidification of the fibers contributed to the maintaining of the 3D structure. Moreover, the 3D silica fibers possessed low bulk densities (16 mg/cm³) and high surface areas (6.5 m²/g), which made them favorable for various applications.