In this study, the effect of nickel, cobalt and titanium dioxide catalysts on the shape and characteristics of sulfur doped carbon structures obtained by CVD has been investigated. Also, for each catalyst, the effect of temperature and effect of time is also examined. In the second study, carbon structures on TiO 2 nanotubes were synthesized to investigate the improvement of photovoltaic properties. The carbon structures obtained in both studies were identified using SEM, EDS, Raman, XRD and TGA.