Synthesis and microstructure of silica nanotubes via a coaxial electrospinning route

In this study, silica nanotubes (SiO₂ NTs) were facilely synthesized via a coaxial electrospinning route. The core-sheath paraffin@PVP-SiO₂ nanofibers (NFs) were firstly prepared through co-axial electrospinning of a sheath-liquid derived from tetraethoxysilane, ethanol, polyvinyl pyrrolidone and hydrogen chloride and a core-liquid of paraffin oil and then sintered at 600°C to produce SiO₂ NTs. The physicochemical property of the SiO₂ NTs was characterized by a SEM machine, a TEM machine and a FT-IR machine. SEM and TEM observations showed that SiO₂ NTs had the diameter of 2320±568 nm with a shell thickness of 303±25 nm and a hollow and tubular structure. FT-IR spectrum showed that SiO₂ NTs had the characteristic peak of Si-O-Si bonds at 1050 cm⁻¹. It was found that the sintering process caused the removal of organic components in paraffin@PVP-SiO₂ NFs and the formation of hollow structure in SiO₂ NTs. (paper)