Efficient Solubilization of Single-Walled Carbon Nanotubes Using Tea Solutions

Abstract

Here we describe the finding that oolong tea and black tea act as excellent carbon nanotube solubilizers to produce individually dissolved single-walled carbon nanotubes (SWNTs), which have been revealed using visible-near IR absorption, photoluminescence and Raman spectroscopy as well as AFM study. The oolong tea solution has a tendency to individually dissolve metallic SWNTs that can be detected by 514 nm-excition, and in solution, the (11,3)SWNTs enriched and (11,0)SWNTs that are contained in as-produced SWNTs were very few. Black tea solution shows similar tendency, while the separation performance was weaker compared to that of the oolong tea. We also used epigallocatechin gallate to solubilize the SWNTs and shed light on the mechanism of the SWNT dissolution. Tea contains numerous components with antioxidant activities; therefore biological and biomedical applications using the present soluble nanotubes might be of interest.