Fabrication of Zn2TiO4 and TiN nanofibers by pyrolysis of electrospun precursor fibers

Abstract

In this paper, Zn₂TiO₄ and TiN nanofibers were prepared by a facile combination of electrospinning followed by thermolysis under different atmospheres. An N,N-dimethyl formamide (DMF)–ethanol solution of poly(vinylpyrrolidone) (PVP), Ti(IV)–isopropoxide (Ti(OC₄H₉)₄) and zinc acetate (ZnAc) was used as the electrospinning precursor and the electrospun nanofibers were calcined at 600 °C in air to generate Zn₂TiO₄ nanofibers. Subsequently, a conversion from Zn₂TiO₄ nanofibers to TiN nanofibers was realized through a heat treatment at 1000 °C under an ammonia atmosphere. Investigations using field-emission scanning electron and transmission electron microscopes (FESEM and TEM) revealed the nano-scale fibrous morphology of the obtained products. Energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD) studies confirmed the chemical composition and crystalline structure of the Zn₂TiO₄ and TiN nanofibers, respectively. The electrochemical properties of the as-prepared TiN nanofibers indicated that the capacitance characteristic of the TiN phase was the electric double-layer capacitance. The value of the specific capacitance gradually decreased with the increase of discharge current density.