基于硅胶快速吸附的碳纳米管长度分选及其晶体管性能研究

Research on Length-Sorting of Carbon Nanotubes Based on Silica Gel Rapid Adsorption and Transistor Performance

摘要:

半导体型单壁碳纳米管在分散与分离过程中长度会被截短。在100nm以下的超短管的存在会增加管间搭接电阻和载流子的散射几率,从而导致器件性能的下降。开发了一种有机体系的硅胶吸附技术。利用硅胶颗粒表面的硅羟基与包裹在碳纳米管表面的聚合物PCz中的N原子形成氢键,成功实现了超短碳管的高效去除,使半导体型碳纳米管的长度分布实现了有效调控。基于长度分选后的碳纳米管制备的晶体管器件,其开态电流和最大跨导达到8.9μA/μm和0.5mS/μm,比长度未分选的器件分别提高了约300%和250%。

Abstract:

The length of semiconducting single-walled carbon nanotubes(s-SWCNTs) is shortened during dispersion and separation. The existence of many ultra-short tubes with length less than 100nm will increase the lap resistance between tubes and increase the scattering probability of carriers, which will lead to the degradation of device performance. It is not beneficial to the development and application of high-performance carbon nanotube devices. However, there is still a lack of research on the separation of s-SWCNTs length in organic system, especially the controllable removal of ultra-short tubes. In this paper, a silica gel adsorption technology in organic system was developed, which successfully achieved the efficient removal of ultra-short carbon nanotubes and effectively regulated the length distribution of semiconducting carbon nanotubes. Prepared by the CNTs with length sorting, the on-state current and maximum transconductance of the transistors were 8.9μA/μm and 0.5mS/μm, which were about 300% and 250% respectively, higher than those of the device without length sorting.