Core-shell-structured carbon nanofiber-titanate nanotubes with enhanced photocatalytic activity

Abstract

Core-shell materials have been developed extensively because of their advanced properties and multifunctionality. Many approaches involving different synthesis techniques have been used for the preparation of various core-shell nanostructures. In this study, we synthesized core-shell-structured carbon nanofiber (CNF)-titanate nanotubes (TiNT) by electrospinning, carbonization, and subsequent alkaline hydrothermal treatment. The CNF core could act as a support, and the TiO2-decorated TiNT shell could act as a photocatalyst. TiNT shells with diameters of several hundreds of nanometers and composed of 10-nm-diameter nanotubes are formed on the CNF surface. The formation of TiNTs on the CNF surface was observed using SEM, HR-TEM, XRD, and XPS analyses. Core-shell-structured CNF-TiNTs exhibited efficient photocatalytic activities for CH3CHO oxidation, which was attributed to the existence of photocatalytically active TiO2-TiNT composites on the CNF surface, which could easily absorb UV light. Additionally, the surface area increase as a result of the alkaline hydrothermal treatment may also be responsible for the efficient photocatalytic activity of core-shell-structured CNF-TiNTs. © 2013 Elsevier B.V.