催化学报 ›› 2011, Vol. 32 ›› Issue (12): 1838-1843.DOI: 10.1016/S1872-2067(10)60288-4

• 研究论文 • 上一篇    下一篇

TiO2/Au 纳米棒阵列的制备及其光催化性能

路莹, 陈硕*, 全燮, 于洪涛   

  1. 大连理工大学环境学院环境工程系, 辽宁大连 116024
  • 收稿日期:2011-08-05 修回日期:2011-09-23 出版日期:2011-12-21 发布日期:2015-04-23

Fabrication of a TiO2/Au Nanorod Array for Enhanced Photocatalysis

LU Ying, CHEN Shuo*, QUAN Xie, YU Hongtao   

  1. Department of Environmental Engineering, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, Liaoning, China
  • Received:2011-08-05 Revised:2011-09-23 Online:2011-12-21 Published:2015-04-23

摘要: 采用电沉积和旋转涂膜相结合的方法成功制备了高度有序的 TiO2/Au 纳米棒阵列催化剂. 扫描电镜和透射电镜结果表明, TiO2 薄膜均匀地包覆在 Au 纳米棒的表面, 形成核壳型的一维阵列结构. X 射线衍射分析表明所获得 TiO2 为 (101) 晶面优先生长的锐钛矿晶相. 紫外-可见漫反射光谱显示, 由于 Au 和 TiO2 间肖特基结的存在造成吸收红移, Au 纳米棒表面的等离子共振效应导致 400~800 nm 间出现吸收峰. 在紫外光催化降解罗丹明 B 反应中, TiO2/Au 纳米棒阵列催化剂表现出优异的催化活性, 其动力学常数分别为 TiO2和 TiO2/Au 膜的 2.0 和 1.3 倍. 这主要归结于 Au 与 TiO2 间的肖特基结和一维阵列结构所带来的大的比表面积、宽的光响应范围和有效的光生载流子分离与传递.

关键词: 二氧化钛, 金纳米棒阵列, 肖特基结, 光生载流子分离, 光生载流子迁移, 光催化活性

Abstract: A highly ordered TiO2/Au nanorod array was successfully fabricated by direct current electrodeposition and subsequent spin-coating. Scanning electron microscopy and transmission electron microscopy images revealed that the TiO2 film completely covered the surface of the Au nanorods, which resulted in TiO2 shell Au core nanorods. X-ray diffraction patterns revealed that the TiO2 film was anatase with preferential orientation in the (101) plane. UV-Vis diffuse reflectance spectra showed a shift in the absorption edge toward the visible region because of the formation of a Schottky junction between Au and TiO2. A new absorption peak that ranged from 400 to 800 nm appeared because of the localized surface plasmon resonance of the Au nanorod arrays. For the photocatalytic degradation of rhodamine B under UV light irradiation, the TiO2/Au nanorod array exhibited excellent photocatalytic activity and its kinetic constant was 2.0 times that of pristine TiO2 and 1.3 times that of a TiO2/Au film. The enhanced photocatalysis was attributed to the high surface volume ratio, an improved UV light response, efficient separation, and the convenient migration of photogenerated charge carriers because of the one-dimensional nanorod structure and the Schottky junction between Au and TiO2. This work could provide new insights into the fabrication of a high performance photocatalyst and thus facilitate practical environmental applications.

Key words: titania, gold nanorod array, Schottky junction, photogenerated charge carrier separation, photogenerated charge carrier migration, photocatalytic activity