Hybrid carbon-TiO2 spheres: Investigation of structure, morphology and spectroscopic studies

Hybrid carbon-TiO2 spheres (TiO2/C spheres) were prepared via the CVD method in the atmosphere of benzene vapours at 800-1000 degrees C. Structure and morphology of prepared hybrid composites were examined by means of SEM, TEM, XPS, TG, Raman spectroscopy, XRD and UV-Vis/DRS methods. The SEM and TEM analysis confirmed the presence of uncovered rutile crystallites as well as the different forms of carbon-modified TiO2 forms: rutile TiO2/C spheres and thin flakes of graphite and thin graphene sheets. The average thickness of the typical spheres varied between 30 and 40 nm for samples prepared at lower temperatures (800-900 degrees C), but the carbon coreshell thickness could be even up to 100 nm for samples obtained at 950-1000 degrees C. The XPS, TG, Raman spectroscopy and XRD measurements allowed to characterize in detail the carbonaceous nature of carbon layers of the fabricated spheres, indicating the graphitic character of TiO2/C hybrids.