Dielectric response of Cr ̵ doped TiO_2 nanoparticles: Effect of doping concentration and annealing temperature

Document Type : Original Article


1 Basic Engineering Science,Faculty of Engineering,Menoufia University,Shebin Elkom, Egypt

2 Basic Engineering Science Department, Faculty of Engineering, Menoufia University, Shebin El-Kom, Egypt

3 Basic Engineering science, faculty of engineering, menoufia university

4 Head Basic Engineering Science/ Faculty of Engineering/ Menoufia University.


The combined effect of doping chromium (Cr) as well as annealing temperature on the dielectric spectroscopy performance of titanium (TiO_2)was investigated. Accordingly, two series of chromium doped titania samples with the form 〖(Ti〗_(1-x) Cr_x O_2) where x=0-25 mol% were fabricated utilizing the hydrolysis method. The first series was used as-synthesized while the second series was used after annealing at 500 ℃ for 1h . The microstructure of both synthesized series was characterized by X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The (XRD) result confirms the formation of the amorphous characteristics of such pure and Cr ̵ doped TiO_2 (as-synthesized) and crystaline characteristics of such pure and Cr ̵ doped TiO_2 (annealed at 500 ℃ for 1h ). The average crystallite size in second series (annealed at 500 ℃) as estimated by the Scherrer’s equation varies in the range of ~12–30 nm on doping of Cr ions in TiO_2. The measured surface area of TiO_2 is decreased by Cr doping in first series (as-synthesized) while it is increased by Cr doping in second series (annealed at 500 ℃). The variation in both dielectric constant (ε^'), and ac conductivity (σ_ac) as a function of applied frequency at different doping concentration of Cr were investigated. The measurements confirms that both ε^' and σ_ac values of TiO_2 were decreased with Cr doping in first series and increased with Cr doping in second series.


Volume 44, Issue 4
Vol. 4 (4) issued on 1/10/2021 is in 5 parts: PART (1) Electrical Engineering, PART(2) Production Engineering PART(3) Civil Engineering PART(4) Architecture Engineering, PART(5) Basic Engineering Sciences.
October 2021
Pages 465-472