Growth of Close-Packed Semiconducting Single-Walled Carbon Nanotube Arrays Using Oxygen-Deficient TiO2 Nanoparticles as Catalysts

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• 作者：Lixing Kang ; Yue Hu ; Lili Liu ; Juanxia Wu ; Shuchen Zhang ; Qiuchen Zhao ; Feng Ding ; Qingwen Li ; Jin Zhang
• 刊名：Nano Letters
• 出版年：2015
• 出版时间：January 14, 2015
• 年：2015
• 卷：15
• 期：1
• 页码：403-409
• 全文大小：434K
• ISSN：1530-6992

文摘

For the application of single-walled carbon nanotubes (SWNTs) in nanoelectronic devices, techniques to obtain horizontally aligned semiconducting SWNTs (s-SWNTs) with higher densities are still in their infancy. We reported herein a rational approach for the preferential growth of densely packed and well-aligned s-SWNTs arrays using oxygen-deficient TiO₂ nanoparticles as catalysts. Using this approach, a suitable concentration of oxygen vacancies in TiO₂ nanoparticles could form by optimizing the flow rate of hydrogen and carbon sources during the process of SWNT growth, and then horizontally aligned SWNTs with the density of 鈭?0 tubes/渭m and the s-SWNT percentage above 95% were successfully obtained on ST-cut quartz substrates. Theoretical calculations indicated that TiO₂ nanoparticles with a certain concentration of oxygen vacancies have a lower formation energy between s-SWNT than metallic SWNT (m-SWNT), thus realizing the preferential growth of s-SWNT arrays. Furthermore, this method can also be extended to other semiconductor oxide nanoparticles (i.e., ZnO, ZrO₂ and Cr₂O₃) for the selective growth of s-SWNTs, showing clear potential to the future applications in nanoelectronics.