In this work, Bi₇O₉I₃/Cd_0.5Zn_0.5S QDs/WO_3−x ternary heterojunction with full spectrum response was prepared and applied in the photodegradation of phenol. The results of photocatalytic experiments showed that the prepared Bi₇O₉I₃/Cd_0.5Zn_0.5S QDs/WO_3−x heterojunction had the highest performance under full spectrum, visible and near-infrared light irradiation, and the reaction rates were 4.02, 3.75 and 5.71 times that of pure Bi₇O₉I₃, respectively. This performance improvement results from the construction of double S-scheme heterojunction and the full-spectrum response, which had effective charge distribution and migration as well as an excellent response to sunlight. In addition,·OH and·O₂^- took the lead role in the process of photodegradation. Combined with the free radical-trapping experiment, ESR experiment and DFT theoretical calculation, the photocatalytic mechanism of double S-scheme system was proposed. This work is contributory to designing novel photocatalytic materials with dual S-scheme heterojunction and the efficient purification of wastewater in environmental remediation.

本工作制备了具有全光谱响应的Bi ₇ O ₉ I ₃ /Cd _0.5 Zn _0.5 S QDs/WO _3-x三元异质结并应用于苯酚的光降解。光催化实验结果表明，制备的Bi ₇ O ₉ I ₃ /Cd _0.5 Zn _0.5 S QDs/WO _3-x异质结在全光谱、可见光和近红外光照射下性能最高，反应速率为4.02。 、纯Bi ₇ O ₉ I _{3的3.75和5.71倍}， 分别。这种性能改进源于双 S 型异质结的构建和全光谱响应，具有有效的电荷分布和迁移以及对阳光的出色响应。此外，·OH和·O ₂ ^-在光降解过程中起主导作用。结合自由基捕获实验、ESR实验和DFT理论计算，提出了双S型体系的光催化机理。这项工作有助于设计具有双 S 型异质结的新型光催化材料和环境修复中废水的有效净化。