Zehtab-Lotfi Elnaz, Amani-Ghadim Ali Reza, Soltani Behzad
Department of Chemistry, Faculty of Science, Azarbaijan Shahid Madani University (ASMU), Tabriz 53751-71379, Iran.
Applied Chemistry Research laboratory, Department of Chemistry, Faculty of Basic Science, Azarbaijan Shahid Madani University (ASMU), Tabriz 53751-71379, Iran.
Dalton Trans. 2022 Aug 16;51(32):12198-12212. doi: 10.1039/d2dt01751b.
Charge carrier recombination and wide band gap energy are still the main challenges in the visible-light-driven photocatalytic applications of titanate perovskites, ATiO. Herein, three strategies are rationally used to achieve a titanate-based photocatalyst with high photocatalytic performance under visible light. In the first step, SrTiO, ZnTiO, and CdTiO perovskites were synthesized and their photocatalytic activity was evaluated in the degradation of methylene blue (MB) and bisphenol A (BPA). Then, a dysprosium cation (Dy) was doped into an ATiO crystalline lattice. Systematic investigations indicate that Dy doping in SrTiO and CdTiO extends the ligand to metal charge transfer absorption edge to visible wavelengths leading to the activation of doped perovskites under visible light. Higher visible-light-driven photocatalytic performance (73.29% for MB and 52.57% for BPA) and higher total organic carbon (TOC) removal (59.20% for MB and 39.53% for BPA) have been achieved by Dy doped CdTiO compared to other photocatalysts. Finally, we prepared a Dy-CdTP/ZnS QD mesoporous type-II heterostructure by the growth of ZnS QDs on a flower-like Dy-CdTP. This design accelerates the separation and transfer of photogenerated electron-hole pairs. The surface area of the Dy-CdTP/ZnS QD heterostructure was ∼11.6 times greater than that of Dy-CdTP, offering a large surface area for the adsorption of organics, and abundant active sites for photocatalytic degradation. Taking advantage of the large surface area and considerable suppressing of the charge carrier recombination, the optimized Dy-CdTP(0.6)/ZnS QD photocatalyst exhibits excellent and stable performance for the degradation of MB (98.25%) and BPA (89.12%) with their considerable mineralization under visible light.
电荷载流子复合和宽带隙能量仍然是钛酸钙钛矿（ATiO）可见光驱动光催化应用中的主要挑战。在此，合理采用了三种策略来制备在可见光下具有高光催化性能的钛酸基光催化剂。第一步，合成了SrTiO、ZnTiO和CdTiO钙钛矿，并在亚甲基蓝（MB）和双酚A（BPA）的降解中评估了它们的光催化活性。然后，将镝阳离子（Dy）掺杂到ATiO晶格中。系统研究表明，Dy掺杂到SrTiO和CdTiO中可将配体到金属的电荷转移吸收边缘扩展到可见光波长，从而导致掺杂钙钛矿在可见光下被激活。与其他光催化剂相比，Dy掺杂的CdTiO实现了更高的可见光驱动光催化性能（MB为73.29%，BPA为52.57%）和更高的总有机碳（TOC）去除率（MB为59.20%，BPA为39.53%）。最后，通过在花状Dy-CdTP上生长ZnS量子点，制备了Dy-CdTP/ZnS QD介孔II型异质结构。这种设计加速了光生电子-空穴对的分离和转移。Dy-CdTP/ZnS QD异质结构的表面积约为Dy-CdTP的11.6倍，为有机物的吸附提供了大表面积，并为光催化降解提供了丰富的活性位点。利用大表面积和对电荷载流子复合的显著抑制，优化后的Dy-CdTP(0.6)/ZnS QD光催化剂在可见光下对MB（98.25%）和BPA（89.12%）的降解表现出优异且稳定的性能，同时具有可观的矿化效果。
