摘要
To further understand the effect of structural defects on the electrochemical and photocatalytic properties of TiO2, two synthetic approaches based on hydrothermal synthesis and post-synthetic chemical reduction to achieve oxygen defect- implantation were developed herein. These approaches led to the formation of TiO2 nanorods with uniformly distributed defects in either the bulk or on the surface, or the combination of both, in the formed TiO2 nanorods (NRs). Both approaches utilize unique TiN nanoparticles as the reaction precursor. Electron microscopy and Brunauer-Emmett-Teller (BET) analyses indicate that all the studied samples exhibit similar morphology and similar specific surface areas. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) data confirm the existence of oxygen defects (Vo). The photocatalytic properties of TiO2 with different types of implanted Vo were evaluated based on photocatalytic H2 production. By optimizing the concentration of Vo among the TiO2 NRs subjected to different treatments, significantly higher photocatalytic activities than that of the stoichiometric TiO2 NRs was achieved. The incident photon-to-current efficiency (IPCE) data indicate that the enhanced photocatalytic activity arises mainly from defect-assisted charge separation, which implies that photo-generated electrons or holes can be captured by Vo and suppress the charge recombination process. The results show that the defective TiO2 obtained by combining the two approaches exhibits the greatest photocatalytic activity enhancement amon~ all the samples.
进一步理解结构的缺点的效果在上电气化学并且 TiO <sub>2</sub>, 的 photocatalytic 性质二条合成途径此处基于热水的合成和 synthetic 以后化学药品减小被开发完成氧 defectimplantation。这些途径在体积或在两个的表面,或联合上与一致地分布式的缺点导致了 TiO <sub>2</sub> nanorods 的形成,在形成的 TiO <sub>2</sub> nanorods (NR ) 。两条途径作为反应先锋利用唯一的听 nanoparticles。电子显微镜学和 Brunauer-Emmett-Teller (赌注) 分析显示所有学习样品展出类似的形态学和类似的特定的表面区域。X 光检查光电子光谱学(XPS ) 和电子顺磁的回声(EPR ) 数据证实氧缺点(VO ) 的存在。有植入的 VO 的不同类型的 TiO <sub>2</sub> 的 photocatalytic 性质基于 photocatalytic H <sub>2</sub> 生产被评估。由在受到不同处理的 TiO <sub>2</sub> NR 之中优化 VO 的集中,显著地更高的 photocatalytic 活动比 stoichiometric TiO <sub>2</sub> NR 的被完成。事件 photon-to-current 效率(IPCE ) 数据显示提高的 photocatalytic 活动主要从帮助缺点的费用分离产生,它暗示产生相片的电子或洞能被 VO 捕获并且压制费用再结合进程。结果证明联合二条途径获得的有缺点的 TiO <sub>2</sub> 在所有样品之中展出最大的 photocatalytic 活动改进。