- - - Department of Condensed Matter Physics, Faculty of Physics, Alzahra University, Tehran, Iran.
- - - Department of Condensed Matter Physics, Faculty of Physics, Alzahra University, Tehran, Iran.

In this research, we synthesized titanium dioxide (TiO۲) nanoparticles by sol-gel method, and doped with different percentages (۰.۲%wt and ۰.۵%wt) of graphite and carbon nanotubes (CNTs). The X-ray diffraction analysis of the samples showed the formation of anatase phase of pure and doped TiO۲ samples. We checked the morphology and grains size of the samples by using FESEM analysis we measured the grain size, which was reduced from ۶۵ nm to ۴۲ nm by doping. The electrical properties of the samples have investigated by LCR meter and measured the capacitance, energy dissipation and conductivity of the samples. The results of the electrical measurements showed that the conductivity of the samples increased from ۵۸.۵۱(Ωm)-۱(*۱۰-۱۲) to ۶۷.۵۲ (Ωm)-۱(*۱۰-۱۲) with doping. We used UV-Vis and FT-IR analysis to investigate optical properties of the samples. We found that CNTs doped samples have more conductivity and smaller grain size than graphite doped samples

titanium dioxide, Carbon nanotubes, Conductivity, Capacitance, Band gap energy