Wet Chemical Synthesis and Optical Properties of Co²⁺-Doped Magnesium Stannate Ceramics

Magnesium stannate (Mg₂SnO₄) samples with 0.003, 0.004, 0.03, 0.05, 0.08, 0.1, 0.2, 0.3, 0.5, 1, 2, and 5 at. mol% of Co²⁺ were prepared by wet chemical method. The samples were investigated using X-Ray diffraction and photoluminescence techniques at room temperature. The results indicate that Co²⁺ occupies tetrahedral sites in the inverse spinel structure of Mg₂SnO₄, replacing Mg²⁺. The material exhibited a red-infrared luminescence associated with Co²⁺ spin-allowed transitions. Crystal field parameters were calculated using Tanabe-Sugano theory for d⁷ systems in tetrahedral environment. In the range studied, optimum divalent cobalt concentration for emission applications was found to be 0.08 at. mol%.

Keywords:
Ceramics; Optical Materials; Chemical Synthesis; Optical Properties; Luminescence