Hybrid structures of gold nanorods and single-walled carbon nanotubes.

摘要

Scope and Method of Study. The purpose of this research is to study optical properties of hybrid structures of nanomaterials such as gold nanorods and single-walled carbon nanotubes (SWNTs). The SWNTs were grafted using polymers via in situ polymerization. The gold nanorods were fabricated using wet-chemical synthesis method. Raman spectroscopy has been employed to characterize pristine SWNTs and hybrid SWNTs. UV-Vis-IR spectrometer was used to evaluate the gold nanorods and nano hybrid structures. Microscopic methods such as TEM, SEM were used distinguishing shapes of gold nanorods and functionalized SWNTs.;Findings and Conclusions. Polystyrene functionalized SWNTs are indicated with clear changes in the D/G ratio (0.336+/-0.005) as compared to pristine SWNTs D/G ratio (0.207+/-0.014). Laser induced changes indicate that the metallic part of the G-mode undergoes a greater change than the semiconductor part. This is due to the preferable oxidation of smaller, more strained SWNTs which, in our case, happen to be metallic ones. Note that only small changes are observed in the D-mode. SWNTs grafted by poly (sodium 4-styrenesulfonate) have been well dispersed in aqueous solution. Through the wet chemical method, we have obtained gold nanorods with aspect ratio 3.4. The shape of gold nanorods have been evaluating with both absorption spectrum and TEM image. The hybrid multilayer films were fabricated using layer-by-layer technique. The Raman spectra showed evidences of functionalization of SWNTs such that increasing intensity of D mode. The hybrid structures of gold nanorods and functionalized SWNTs have been built in aqueous solution. We observed red-shift of longitudinal plasmon absorption peak of gold nanorods while mixing gold nanorods and functionalized SWNTs in aqueous solution. Using spectral evidences, we can evaluate that the gold nanorods have been aligned on surface of the functionalized SWNTs because the surface have opposite electrostatic charges.