Role of SrCO 3 on Photocatalytic Performance of SrTiO 3 -SrCO 3 Composites.

Perovskites such as SrTiO₃ are interesting for photocatalytic applications due to their structure-related and electronic properties. These properties are influenced by the presence of SrCO₃ which is often formed simultaneously during the hydrothermal synthesis of SrTiO₃. In this study, SrTiO₃-SrCO₃ composites with different contents of SrCO₃ (5–24 wt%) were synthesized. Their morphological, structural, and optical properties were investigated using complementary methods such as scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen sorption, and diffuse reflectance spectroscopy (DRS). Their photocatalytic activity was assessed during the degradation of diclofenac (DCFNa) in aqueous solution and CO₂ photoreduction under Xe lamp irradiation. Improved photocatalytic efficiency in DCFNa degradation was observed for all the studied composites in comparison with SrTiO₃, and the highest mineralization efficiency was obtained for the sample with 21 wt% SrCO₃ content. The presence of SrCO₃ led to an increased concentration of active species, such as ^•OH radicals. Otherwise, its presence inhibits CH₄ and C₂H₆ production during CO₂ photoreduction compared with pure SrTiO₃. [ABSTRACT FROM AUTHOR]