College of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, China; Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.
Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.
J Colloid Interface Sci. 2022 Dec 15;628(Pt B):614-626. doi: 10.1016/j.jcis.2022.08.089. Epub 2022 Aug 17.
A novel three-dimensional (3D) S-scheme S-gCN/TiO/SiO/PAN aerogel heterojunction photocatalyst (denoted as S-gTAHP) is rationally devised and manufactured by combining electrospinning, calcination, hydrothermal and freeze-drying techniques. The synthesized S-gCN molecule is different from traditional g-CN, which has a small molecular structure similar to melamine. S-gCN is embedded in the interwoven network structure of TiO/PAN short fibers, and the catalytic system of the S-scheme heterojunction is formed with SiO as a crosslinking agent. S-gTAHP achieves perfect tri-functional photocatalytic capability, including remarkable hydrogen release capacity (806.7 μmol∙h∙g), efficient removal of three colored dyes with removal efficiencies up to 99.43% (MB, 15 min), 96.13% (RhB, 30 min) and 91.32% (MO, 40 min), and a degradation rate of the colorless antibiotic TCH reaching 84.20% in 40 min driven by simulated sunlight. Meanwhile, the effects of pH values and concentrations of contaminant solutions on the removal rates are explored, and the S-scheme mechanism of S-gTAHP strengthening photocatalytic activity is elucidated. The apparently heightened photocatalytic activities of S-gTAHP can be ascribed to the fact that the 3D hierarchical porous structure of the aerogel endows more active centers and enhanced light-harvesting capacity, and the S-scheme heterojunction supplies effective charge migrating channels, thereby affording the carriers with strong redox capability. Furthermore, S-gTAHP holds prominent reusability and is light weight. Hence, efficient and recyclable 3D aerogel photocatalysts with S-scheme heterojunctions have broad application prospects in practical sewage treatment and energy conversion fields.
一种新型的三维（3D）S 型 S 型 gCN/TiO/SiO/PAN 气凝胶异质结光催化剂（记为 S-gTAHP）通过静电纺丝、煅烧、水热和冷冻干燥技术合理设计和制造。合成的 S-gCN 分子不同于传统的 g-CN，它具有类似于三聚氰胺的小分子结构。S-gCN 嵌入 TiO/PAN 短纤维的交织网络结构中，以 SiO 作为交联剂形成 S 型异质结催化体系。S-gTAHP 实现了完美的三功能光催化能力，包括显著的氢气释放能力（806.7 μmol·h·g）、高效去除三种有色染料，去除效率高达 99.43%（MB，15 分钟）、96.13%（RhB，30 分钟）和 91.32%（MO，40 分钟），以及在模拟阳光下驱动下无色抗生素 TCH 的降解率在 40 分钟内达到 84.20%。同时，还探索了 pH 值和污染物溶液浓度对去除率的影响，并阐明了 S-gTAHP 增强光催化活性的 S 型机制。S-gTAHP 明显提高的光催化活性可以归因于气凝胶的 3D 分级多孔结构赋予了更多的活性中心和增强的光捕获能力，以及 S 型异质结提供了有效的电荷迁移通道，从而赋予载体强大的氧化还原能力。此外，S-gTAHP 具有突出的可重复使用性和重量轻。因此，具有 S 型异质结的高效、可回收的 3D 气凝胶光催化剂在实际污水处理和能量转换领域具有广阔的应用前景。
