Authors: R. Paul, P. Kumbhakar, A.K. Mitra
Affilation: NIT Durgapur India, India
Pages: 304 - 307
Keywords: SWCNT, TiO2, nanohybrid, photoluminiscence
Using a lucid wet chemical process under room temperature, titania nanocrystallites of average size 5 nm have been adhered to the surfaces of SWCNT bundles. The hybrid structure has been characterized by high resolution transmission electron microscopy (HRTEM), x-ray diffractogram (XRD), energy dispersive x-ray spectroscopy analysis (EDAX) and Raman spectroscopy. From the HRTEM micrograph, it is clearly revealed that titania nanocrystals of nearly uniform size adhered to the SWCNT surfaces. The presence of titania has been confirmed from EDAX analysis. Raman spectroscopy shows additional peaks of TiO2 nanocrystals in the range 150-700 cm-1. The UV-vis study shows that there is a blue shift by 16 nm in the absorption peak position of the hybrid structure with respect to that of the pristine SWCNT. The absorption intensity of the TiO2- coated SWCNT degraded possibly due to increased scattering in the nanohybrid structure. The hybrid structure showed violet-blue emission when excited by UV radiation of wavelength 220-260 nm. The photoluminescence emission of the hybrid structure is attributed to the charge transfer between titania nanocrystals and carbon nanotubes. This material may find wide applications in sensor based devices.