Abstract We investigated a new method for the preparation of visible light-activated heterostructured photocatalysts made up of SrTiO3 (STO) and g-C3N4 (CN). The photocatalysts were synthesized by the polymeric precursor method to obtain STO, which was further thermally treated at 550 °C for 2 h in presence of melamine at different proportions for CN formation. The SrTiO3/g-C3N4 heterostructures were termed as STOCN-Mel88%, STOCN-Mel92%, STOCN-Mel95%, STOCN-Mel97% and STOCN-Mel99% indicating the use of melamine at 88%, 92%, 95%, 97% or 99%. The SrTiO3/g-C3N4 heterostructures were characterized for their crystalline structure, optical properties, thermal stability, morphology and surface composition, and photocatalytic potential, which was evaluated by photodegradation of methylene blue dye and amiloride under visible light. The melamine content exhibited a strong influence on the formation of CN, as well as on the bulk structure, surface and photocatalytic properties of the SrTiO3/g-C3N4 heterostructures. The heterostructures were catalytically active under visible light due to their reduced band gap energy. The presence of oxygen vacancies in the STO phase associated with the CN phase improved the photogenerated electron-hole charge separation in the SrTiO3/g-C3N4 catalysts. The synthesis described here is efficient in obtaining visible light-activated photocatalysts that are applicable to photocatalytic processes under solar light.

中文翻译：

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用于可见光诱导光催化的 SrTiO3/g-C3N4 异质结构的制备

摘要 我们研究了一种制备由 SrTiO3 (STO) 和 g-C3N4 (CN) 组成的可见光活化异质结构光催化剂的新方法。光催化剂通过聚合前体法合成得到 STO，然后在不同比例的三聚氰胺存在下，在 550°C 下进一步热处理 2 小时以形成 CN。SrTiO3/g-C3N4 异质结构被称为 STOCN-Mel88%、STOCN-Mel92%、STOCN-Mel95%、STOCN-Mel97% 和 STOCN-Mel99%，表明使用了 88%、92%、95%、97 的三聚氰胺% 或 99%。SrTiO3/g-C3N4异质结构的晶体结构、光学性质、热稳定性、形貌和表面组成以及光催化潜力被表征，通过可见光下亚甲基蓝染料和阿米洛利的光降解来评估。三聚氰胺含量对CN的形成以及SrTiO3/g-C3N4异质结构的本体结构、表面和光催化性能有很大影响。由于带隙能量降低，异质结构在可见光下具有催化活性。与 CN 相相关的 STO 相中氧空位的存在改善了 SrTiO3/g-C3N4 催化剂中的光生电子-空穴电荷分离。这里描述的合成在获得适用于太阳光下光催化过程的可见光活化光催化剂方面是有效的。由于带隙能量降低，异质结构在可见光下具有催化活性。与 CN 相相关的 STO 相中氧空位的存在改善了 SrTiO3/g-C3N4 催化剂中的光生电子-空穴电荷分离。这里描述的合成在获得适用于太阳光下光催化过程的可见光活化光催化剂方面是有效的。由于带隙能量降低，异质结构在可见光下具有催化活性。与 CN 相相关的 STO 相中氧空位的存在改善了 SrTiO3/g-C3N4 催化剂中的光生电子-空穴电荷分离。这里描述的合成在获得适用于太阳光下光催化过程的可见光活化光催化剂方面是有效的。