Dielectric and photoluminescence properties of Nd and Ga codoped-BaTiO3, prepared by sol–gel method

Neodymium and gallium codoped barium titanate (Ba 1−x−y Nd x Ga y TiO 3 , x = 0.03, 0.05, 0.07, 0.1 and y = 0.03) were prepared by sol–gel method in order to investigate its dielectric and photoluminescence properties. The structure and morphology of Ba 1−x−y Nd x Ga y TiO 3 powders calcined at 1100 °C and sintered ceramics by spark plasma sintering (SPS) technique were analyzed using X-ray diffraction and scanning electron microscope, respectively. The photoluminescence and dielectric properties of Nd doped Ba 0.97 Ga 0.03 TiO 3 , (y = 0.03) as a function of Nd 3+ concentration and sintering temperature were also investigated. The influence of Ga 3+ and Nd 3+ dopants on the crystalline phases, sintering process by SPS and macroscopic properties of Ba 1−x−y Nd x Ga y TiO 3 ceramics was analyzed, as well as a weak hot emission from the 4F5/2 level. The sintered ceramics showed high dielectric constant and moderate dielectric losses. The highest value of the permittivity obtained for Ba 1−x−y Nd x Ga y TiO 3 ceramics was ɛ r = 5890 at room temperature, 1 kHz and x = y = 0.03. This study shown that Nd 3+ decreases the density of the pellets, increases the dielectric losses and decreases the dielectric constant of Ba 0.97 Ga 0.03 TiO 3 ceramics. Therefore, the values of dielectric properties, at room temperature, of BaTiO 3 doped with 3 at.% Ga and ≤7 at.% Nd are higher than those of undoped BaTiO 3 ceramic.