Aligned rutile TiO2 nanorods: Facile synthesis and field emission

• Two-step technique for the formation of aligned TiO2 nanorods (TNRs) was developed.
• The aligned TNRs are rutile phase with a preferential growth direction of [1 1 0].
• The structure parameters of TNRs can be easily adjusted by the anodization times.
• The turn-on field can drop to 1.78 V/μm by adjusting anodization times.

By simple two-step technique, first anodization in an ethylene glycol solution and then oxidation in a low-pressure atmosphere by chemical vapor deposition at 750 °C, aligned rutile TiO2 nanorods (TNRs) were successfully synthesized. Furthermore, their growth mechanism and field-emission (FE) property were experimentally investigated. The results indicate that the aligned TNRs are rutile phase with a preferential growth direction of [1 1 0] and their structure parameters such as the aspect ratio and density can be easily adjusted by the anodization times, which are beneficial for optimizing their FE properties. When the anodization time increases from 30 to 480 s, the nanorods show various aspect ratios in a range of 16–28 and different turn-on fields within 1.78–6.46 V/μm. The optimized sample of anodized 120 s exhibits excellent FE properties involving both a low turn-on field of 1.78 V/μm, a high field enhancement factor (4757) and a good FE stability.

Single crystal TiO2 nanorods are prepared by simple two-step technique and their field emission properties are optimized. A low turn-on field of 1.78 V/μm and a high field enhancement factor 4756.69 are obtained.Figure optionsDownload as PowerPoint slide