Preparation of pod-shaped TiO2 and Ag@TiO2 nano burst tubes and their photocatalytic activity

Abstract

The pod-shaped TiO₂ nano burst tubes (TiO₂ NBTs) were prepared by the combination of electrospinning and impregnation calcination with oxalic acid (H₂C₂O₄), polystyrene (PS) and tetrabutyl titanate. The silver nanoparticles (AgNPs) were loaded onto the surface of TiO₂ NBTs by ultraviolet light reduction method to prepare pod-shaped Ag@TiO₂ NBTs. In this work, we analysed the effect of the amount of oxalic acid on the cracking degree of TiO₂ NBTs; the effect of the concentration of AgNO₃ solution on the particle size and loading of AgNPs on the surface of TiO₂ NBTs. Scanning electron microscopy and transmission electron microscopy investigated the surface morphology of samples. X-ray diffraction and X-ray photoelectron spectroscopy characterized the structure and composition of samples. Rhodamine B (RhB) solution was used to evaluate the photocatalytic activity of pod-shaped TiO₂ NBTs and Ag@TiO₂ NBTs. The results showed that TiO₂ NBTs degraded 91.0% of RhB under ultraviolet light, Ag@TiO₂ NBTs degraded 95.5% under visible light for 75 and 60 min, respectively. The degradation process of both samples was consistent with the Langmuir-Hinshelwood first-order kinetic equation. Therefore, the catalytic performance of the sample is: Ag@TiO₂ NBTs > TiO₂ NBTs > TiO₂ nanotubes.

Keywords: TiO2; morphology control; nanocomposites; photocatalysis; pod-shaped.