Gao Xin, Liu Xiangxuan, Wang Xuanjun, Zhu Zuoming, Xie Zheng, Li Jun
High-Tech Institute of Xi'an, Shaanxi, 710025, China.
High-Tech Institute of Beijing, Beijing, 100085, China.
Nanoscale Res Lett. 2016 Dec;11(1):496. doi: 10.1186/s11671-016-1718-9. Epub 2016 Nov 10.
Photocatalysis technology could utilize solar energy to degrade many toxic pollutants and provides possibility to deal with unsymmetrical dimethylhydrazine (UDMH) wastewater with less energy consumption. In this study, well-aligned TiO nanorod arrays (TiO NRAs) were grown directly on transparent conductive glass (FTO) via a hydrothermal method, and TiO NRAs/CdS heterostructure films were prepared by decorating TiO NRAs with CdS nanoparticles through successive ion layer adsorption and reaction (SILAR). Under visible light, the TiO NRAs/CdS heterostructure displays enhanced photodegrading capacity compared with the bare TiO NRAs, and the highest photodegradation rate, 27.5% higher than that of the bare TiO NRAs, was achieved by the sample with 15 SILAR cycles. Additionally, the solution pH had some influence on the degradation process, which shows that the best degradation rate can be achieved in the neutral solution (pH is ca. 7.2), and the photodegradation process can be better in alkaline solution than in the acid solution. Moreover, the visible photocatalytic stability of the TiO NRAs/CdS sample was investigated. Finally, the underlying photocatalytic mechanism was discussed according to the photoelectrochemical and photoluminescence results.
光催化技术可以利用太阳能降解多种有毒污染物，并为以较低能耗处理偏二甲肼（UDMH）废水提供了可能性。在本研究中，通过水热法在透明导电玻璃（FTO）上直接生长了排列规整的TiO纳米棒阵列（TiO NRAs），并通过连续离子层吸附和反应（SILAR）法用CdS纳米颗粒修饰TiO NRAs制备了TiO NRAs/CdS异质结构薄膜。在可见光下，TiO NRAs/CdS异质结构相比于裸露的TiO NRAs表现出增强的光降解能力，通过15次SILAR循环的样品实现了最高的光降解率，比裸露的TiO NRAs高27.5%。此外，溶液pH值对降解过程有一定影响，这表明在中性溶液（pH约为7.2）中可实现最佳降解率，且在碱性溶液中的光降解过程优于酸性溶液。此外，还研究了TiO NRAs/CdS样品的可见光光催化稳定性。最后，根据光电化学和光致发光结果讨论了潜在的光催化机理。
