Department of Physics and Hybrid Nanostructure Research Lab, Korea University, Seoul 136-713, Korea.
ACS Nano. 2010 Jul 27;4(7):4197-205. doi: 10.1021/nn100427f.
We fabricate hybrid coaxial nanotubes (NTs) of multiwalled carbon nanotubes (MWCNTs) coated with light-emitting poly(3-hexylthiophene) (P3HT). The p-type P3HT material with a thickness of approximately 20 nm is electrochemically deposited onto the surface of the MWCNT. The formation of hybrid coaxial NTs of the P3HT/MWCNT is confirmed by a transmission electron microscope, FT-IR, and Raman spectra. The optical and structural properties of the hybrid NTs are characterized using ultraviolet and visible absorption, Raman, and photoluminescence (PL) spectra where, it is shown that the PL intensity of the P3HT materials decreases after the hybridization with the MWCNTs. The current-voltage (I-V) characteristics of the outer P3HT single NT show the semiconducting behavior, while ohmic behavior is observed for the inner single MWCNT. The I-V characteristics of the hybrid junction between the outer P3HT NT and the inner MWCNT, for the hybrid single NT, exhibit the characteristics of a diode (i.e., rectification), whose efficiency is clearly enhanced with light irradiation. The rectification effect of the hybrid single NT has been analyzed in terms of charge tunneling models. The quasi-photovoltaic effect is also observed at low bias for the P3HT/MWCNT hybrid single NT.
我们制备了发光聚(3-己基噻吩)(P3HT)涂覆的多壁碳纳米管(MWCNT)的混合同轴纳米管(NTs)。厚度约为 20nm 的 p 型 P3HT 材料通过电化学沉积在 MWCNT 的表面上。通过透射电子显微镜、FT-IR 和拉曼光谱证实了 P3HT/MWCNT 混合同轴 NT 的形成。使用紫外可见吸收、拉曼和光致发光(PL)光谱来表征混合 NT 的光学和结构特性,结果表明 PL 强度在与 MWCNTs 杂交后降低了 P3HT 材料。外 P3HT 单 NT 的电流-电压(I-V)特性表现出半导体行为,而内单 MWCNT 则表现出欧姆行为。对于混合单 NT,外 P3HT NT 和内 MWCNT 之间的混合结的 I-V 特性表现出二极管的特性(即整流),其效率随着光照射明显增强。根据电荷隧道模型分析了混合单 NT 的整流效果。在低偏压下,还观察到了 P3HT/MWCNT 混合单 NT 的准光伏效应。