Reddy Kakarla Raghava, Nakata Kazuya, Ochiai Tsuyoshi, Murakami Taketoshi, Tryk Donald A, Fujishima Akira
Kanagawa Academy of Science and Technology, KSP Bldg. East 412 3-2-1 Sakado, Takstsu-Ku, Kawasaki, Kanagawa 213-0012, Japan.
J Nanosci Nanotechnol. 2011 Apr;11(4):3692-5. doi: 10.1166/jnn.2011.3805.
A novel chemical method has been developed for the fabrication of Ag nanoparticles-coated TiO2 nanofiber composites. The method involves dispersion of TiO2 nanofibers in silver salt solution under ultrasonication, followed by addition of sodium citrate as a reducing agent. The Ag-coated TiO2 composites were characterized by high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and X-ray photoelectron microscopy (XPS). Furthermore, the photocatalytic performance was evaluated by the photocatalytic degradation of methyl orange under UV-light irradiation. It was found that the heterogeneous Ag-TiO2 composite showed a higher activity than the pure TiO2 nanofiber; the enhanced activity can be attributed to the excellent distribution and interaction of Ag nanoparticles with the TiO2 nanofiber support. A plausible mechanism for the formation of the Ag-coated TiO2 composite and reasons for the enhancement of photocatalytic activity are also discussed.
已开发出一种用于制备银纳米颗粒包覆二氧化钛纳米纤维复合材料的新型化学方法。该方法包括在超声作用下将二氧化钛纳米纤维分散于银盐溶液中，随后加入柠檬酸钠作为还原剂。通过高分辨率透射电子显微镜（HRTEM）、X射线衍射（XRD）和X射线光电子显微镜（XPS）对银包覆二氧化钛复合材料进行了表征。此外，通过在紫外光照射下光催化降解甲基橙来评估其光催化性能。结果发现，异质Ag-TiO₂复合材料比纯二氧化钛纳米纤维表现出更高的活性；活性增强可归因于银纳米颗粒与二氧化钛纳米纤维载体的优异分布和相互作用。还讨论了形成银包覆二氧化钛复合材料的合理机制以及光催化活性增强的原因。
