Hierarchical electrospun SiO₂ nanofibers containing SiO₂ nanoparticles with controllable surface-roughness and/or porosity

Herein we report that hierarchical electrospun SiO₂ nanofibers incorporated with SiO₂ nanoparticles with fiber diameters being ∼ 500 nm and particle sizes being tens of nanometers were developed through the combination of sol-gel process and electrospinning technique followed by high-temperature pyrolysis; and their morphologies and BET surface areas were examined. The study revealed that the pre-gelation of tetraethyl orthosilicate (TEOS) in spin dopes was important to achieve the morphological consistence of the electrospun precursor nanofibers and the resulting final SiO₂ nanofibers; additionally, SiO₂ nanoparticles appeared to be enriched on the fiber surface, while the surface-roughness and/or porosity of the nanofibers could be controlled through adjusting the incorporation amount of SiO₂ nanoparticles. The developed hierarchical electrospun SiO₂ nanofibers are expected to have important applications in composites (particularly dental composites) as well as catalyst support and adsorption.