Development of optimized triaxially electrospun titania nanofiber‐in‐nanotube core‐shell structure

Abstract One dimensional (1D) nanostructures and its derivatives can be manipulated to serve special functions like hollow structure, and higher surface area. 1D TiO 2 nanotube‐in‐nanofibers (NF@NT) are developed through triaxial electrospinning followed by a calcination process. A blended solution of polyvinyl pyrrolidone and tetra ‐butyl titanate is used in outer and inner layers of nanofibers, respectively, while paraffin oil is used in the middle layer. The optimized triaxial nanofibers of 669.4 ± 52.43 nm are developed at 7.5 w/w% concentration, 28 kV applied voltage, and 24 cm spinning distance. TiO 2 NF@NT structure is obtained through calcination of optimized triaxial nanofibers at 550°C. Subsequently, the morphology of TiO 2 NF@NT and its uniform diameter distribution is confirmed through scanning electron microscopy. Fourier‐transform infrared spectroscopy results indicates the formation of TiO 2 NF@NT. X‐Rays diffraction pattern peaks also reveals the presence of both anatase and rutile crystalline phases. The presence of only titanium (Ti) and oxygen (O) elements in the TiO 2 NF@NT is confirmed through energy dispersive X‐ray spectroscopy. Brunauer–Emmett–Teller analysis indicates that TiO 2 NF@NT has a higher specific surface area of ~141.68 m 2 /g compared with the solid TiO 2 nanofiber (~75.31 m 2 /g). This study can be adopted to develop TiO 2 NF@NT for wide range of application.