CNT facilitated interfacial charge transfer of TiO2 nanocomposite for controlling the electron-hole recombination

Abstract

We studied the nucleation and growth of TiO2 nanoflowers and carbon nanotubes-TiO2 nanocomposite (n-CNT-TiO2) by the hydrothermal method in a single step at 150 °C and tested them for the photocatalytic degradation of MB. The microstructural analysis confirmed the transformation of TiO2 nanoflowers to CNT-TiO2 spheres due to the role of surface energy of CNT. The XRD peak profile analysis of TiO2 and n-CNT-TiO2 confirmed the formation of pure rutile phase of Titania sintered at 400 °C. A red-shift in the bandgap of n-CNT-TiO2 nanocomposite (2.7eV) was observed due to the donor states towards the conduction band edge. The core-level of XPS showed the strong interaction between carbon and titanium atoms. The CNT facilitate the interfacial charge transfer or avoid the formation of charge recombination due to the variation of Ti4+ to Ti3+ sites. The highest photocatalytic degradation was achieved by using the photocatalyst of n-CNT-TiO2 nanocomposite. The incorporation of CNT provides the interfacial charge transfer facility that creates new interbands energy states for the delay of electron-hole recombination, which cater the environmental remediation.