Highly active ZnO rod-like nanomaterials: Synthesis, characterization and photocatalytic activity for dye removal
- 作者：Hoda S. Hafez hoda_hafez2@yahoo.com
- 刊名：Physica E
- 出版年：2012
- 期刊代码：139_13869477
- 类别：et
- 出版时间：April-May, 2012
- 卷：44
- 期：7-8
- 页码：1522-1527
- 文件大小：645 K
摘要
Highly active ZnO rod-like nanostructures with pointed-shape ends have been synthesized via a simple hydrothermal method using acetic acid as an organic capping agent. The X-ray diffraction (XRD) pattern of the prepared sample reveals that the ZnO rod-like nanostructures are of pure hexagonal wurtzite structure. Morphology of the nanorods has been investigated by transmission electron microscope (TEM), which showed the formation of pointed nanorods of 30-50 nm in diameter and 400-650 nm in length. Optical properties have been investigated by UV-vis diffuse reflectance and photoluminescence spectroscopy. UV-vis absorption spectrum indicated that the ZnO nanorods have higher visible light harvesting as compared to the other morphologies in the literature. Intense room temperature green-red photoluminescence peaks at 486 nm and 564 nm has been observed for the prepared ZnO. This gives a good evidence of the presence of ionized oxygen vacancies which are favorable for photocatalytic reactions. The BET surface area and the average (BJH) adsorption pore size were 269.86 m2/g and 2.86 nm, respectively. The photocatalytic activity of the prepared sample was tested on the degradability of an industrial textile dye, Reactive Yellow 15 (Yellow GR), under sunlight irradiation. A 85.7%dye removal was achieved by applications of these rod-like nanostructures as a photocatalyst.
The reusability of the synthesized ZnO nanomaterial has been investigated under the same experimental conditions for three time to evaluate the photoactivity of the photocatalyst.