Photocatalytic performance of Z-scheme SrCO3-SrTiO3/Ag3PO4 heterojunction for tetracycline hydrochloride degradation

Visible-light-driven photocatalysis, as an emerging environmental restoration technology, has become a focus of attention recently. In this work, a novel SrCO3-SrTiO3/Ag3PO4 heterojunction was successfully synthesized, and its structure, composition, and optical performance were systematically characterized. In addition, SrTiO3/Ag3PO4 was also synthesized, and its type II heterojunction had certain defects. The active species trapping experiments of SrCO3–SrTiO3/Ag3PO4 showed that ·OH and ·O2− participated during the reaction. The photodegradation efficiency of SrCO3–SrTiO3/Ag3PO4 heterojunction was 1.4 times and 2.0 times that of Ag3PO4 and SrCO3–SrTiO3, respectively. A novel Z-scheme mechanism could be used to explain the photoreaction process of SrCO3–SrTiO3/Ag3PO4. The excellent photocatalytic property was due to the enhancement of visible-light absorption, the effective separation of photogenerated charges, and the generation of abundant active species.