Tailored fabrication of TiO2@carbon nanofibers composites via foaming agent migration

Abstract

Based on the merits and demerits of conventional methods for fabricating TiO₂@carbon nanofibers (TiO₂@CNFs) composites, the composites were prepared via a foaming-assisted electrospinning strategy and subsequent thermal treatment. Betaine was used as the foaming agent and assembled with TiO₂ before electrospinning. It was found that the foaming agent of betaine introduced within the solutions played a crucial role on the migration of TiO₂ nanoparticles to the surface of CNFs, enabling their regular movement when the carbonization temperature increased from 400 to 1000 °C. The TiO₂ loading amount on the surface of CNFs increased gradually with an enhanced temperature, resulting in an increase in specific surface area from 30.09 to 419.8 m² g⁻¹. In addition, the obtained TiO₂@CNFs composites exhibited excellent hydrophilicity and high degree of graphitization. Accordingly, when the carbonization temperature increased, the composites presented an enhanced photocatalytic activity toward the degradation of rhodamine B. Hence, a novel method for preparing TiO₂@CNFs composites with tailored TiO₂ loading amount could be envisioned.