ABSTRACT

The homogeneous Cu–ZnO and heterogeneous Ag/ZnO nanorods were synthesised by controlling the ionic radius of Cu and Ag with lattice of ZnO. The structure of Cu–ZnO and Ag/ZnO was investigated by a series of methods. The study of the photoelectric properties suggested both the homogeneously and heterogeneously doped ZnO displayed an increased photocatalytic performance. It was worth noting that the Cu–ZnO and Ag/ZnO composites shown different degradation activities of methylene blue under the visible and UV light irradiation. The data suggested that the Cu species incorporated into the crystal lattice of ZnO nanorods could promote the utilisation of visible light, leading to 2.5- and 2.7-fold increase in the degradation rates compared with Ag/ZnO and ZnO nanorods. However, when UV light was employed, on the one hand, the significant increase of the activity for both Cu–ZnO and Ag/ZnO compared with ZnO was observed and on the other hand, the degradation rate of Cu–ZnO was close to that of Ag/ZnO. The investigation suggested that the metallic Cu in the ZnO crystal lattice could promote the separation of electrons and holes generated by ZnO under visible light. As for the UV light, both doping styles could favour the separation process. The present work could provide a further insight for the design of ZnO-based nanomaterials and development of their applications in environmental catalysis.

摘要

通过控制 Cu 和 Ag 的离子半径以及 ZnO 的晶格来合成均质的 Cu-ZnO 和异质的 Ag/ZnO 纳米棒。通过一系列方法研究了Cu-ZnO和Ag/ZnO的结构。光电性质的研究表明，均相和异相掺杂的 ZnO 均显示出提高的光催化性能。值得注意的是，Cu-ZnO 和 Ag/ZnO 复合材料在可见光和紫外光照射下表现出不同的亚甲基蓝降解活性。数据表明，掺入 ZnO 纳米棒晶格中的 Cu 物质可以促进可见光的利用，与 Ag/ZnO 和 ZnO 纳米棒相比，降解速率提高了 2.5 倍和 2.7 倍。然而，当使用紫外线时，一方面，观察到与 ZnO 相比，Cu-ZnO 和 Ag/ZnO 的活性显着增加，另一方面，Cu-ZnO 的降解速率接近 Ag/ZnO。研究表明，ZnO晶格中的金属Cu可以促进ZnO在可见光下产生的电子和空穴的分离。至于紫外光，两种掺杂方式都有利于分离过程。目前的工作可以为 ZnO 基纳米材料的设计及其在环境催化中的应用开发提供进一步的见解。研究表明，ZnO晶格中的金属Cu可以促进ZnO在可见光下产生的电子和空穴的分离。至于紫外光，两种掺杂方式都有利于分离过程。目前的工作可以为 ZnO 基纳米材料的设计及其在环境催化中的应用开发提供进一步的见解。研究表明，ZnO晶格中的金属Cu可以促进ZnO在可见光下产生的电子和空穴的分离。至于紫外光，两种掺杂方式都有利于分离过程。目前的工作可以为 ZnO 基纳米材料的设计及其在环境催化中的应用开发提供进一步的见解。