Selective Extraction of Semiconducting Single-Wall Carbon Nanotubes by Poly(9,9-dioctylfluorene-alt-pyridine) for 1.5 μm Emission

For applications in standard optical devices, single-wall carbon nanotubes (SWCNTs) exhibiting emissions near 1500 nm are potentially feasible because silicon semiconductors efficiently transmit the light in this region. However, techniques to extract such semiconducting SWCNTs have not been reported thus far. In this study, using poly(9,9-dioctylfluorene-alt-pyridine) (PFOPy) as a dispersant in organic solvent, we succeeded in selectively dispersing SWCNTs which show near-infrared fluorescence around 1500 nm. On the basis of optical absorption and photoluminescence excitation spectroscopy, we revealed that the outstanding tube-structure preference of PFOPy can be interpreted by a characteristic "wavy" conformation of PFOPy on the tube wall.