Regular Article

Hydrogenation shrinks the colossal permittivity of Sb/Co co-doped TiO₂ nanoparticles-structural and optical investigations

Department of Physics, College of Science, University of Bahrain, P.O. Box 32038, Kingdom of Bahrain

^* e-mail: adakhil@sci.uob.bh

Received: 2 September 2022
Received in final form: 9 November 2022
Accepted: 9 December 2022
Published online: 13 January 2023

Abstract

Pristine and (Sb/Co)-codoped TiO₂ anatase powders were synthesized by hydrothermal method and some of the samples were hydrogenated. The samples were characterized by the traditional techniques: X-rays, optical diffuse reflection spectroscopy (DRS), and ac-electrical measurements. It was observed that the (Sb/Co) codoping induces the growth of the anatase. The optical absorption investigation was clarified by the generation of an intermediate band in the bandgap of TiO₂. The catalysis power of the Co²⁺ ions to the adsorbed H₂-dissociation strongly supports the optical absorption strength. The Sb⁵⁺/Co²⁺ codoping could generate weak colossal permittivity, which was lowered by ∼50% with hydrogenation. Such important results was studied and explained.