Molten Salt Synthesis of SrTiO₃ Using TiO₂ with Different Morphology as a Precursor

Abstract

SrTiO₃ powders were synthesized by molten salt method with homemade different morphology TiO₂ in the eutectic NaCl-KCl salts. The phases, crystallite sizes, morphologies and band gap of the as-prepared products were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectra respectively. The photocatalytic activity of SrTiO₃ with different morphology was measured by CO₂ reduction device. The morphologies of the as-synthesized SrTiO₃ depended on the morphologies of TiO₂ precursors, indicating that the formation process of SrTiO₃ in the molten salts was mainly controlled by the template formation mechanism. The results show that compared with different morphology SrTiO₃, sphere-shaped SrTiO₃ exhibit best activity loaded 5%Cu, showed the least Eg and crystallite size. The photocatalytic activity has something to do with the crystallite and the Eg with different morphology.

Keywords:

• SrTiO₃
• molten salt synthesis
• photocatalysis
• CO₂ reduction