(Invited) Transport and Emission Properties of Polymer-Sorted Monochiral and Mixed Carbon Nanotube Networks

Abstract

The selective dispersion of semiconducting carbon nanotubes (s-SWNT) by wrapping with conjugated polymers has enabled their application in electronic and optoelectronic devices such as field-effect transistors and light-emitting field-effect transistors. Here, we show that the dispersion process can be easily scaled-up while maintaining good photoluminescence yield (2%) and nanotube length (>1 µm) to obtain concentrated dispersions and ultimately thin (<10 nm) or thick films (>100 nm) of s-SWNT with excellent optical and electrical properties. We demonstrate ambipolar charge transport and near-infrared light-emission in field-effect transistors based on monochiral and mixed networks of s-SWNT and investigate the influence of the nanotube diameter distribution on charge transport within the network depending on the applied gate voltage and thus charge carrier density. Voltage-dependent photoluminescence and electroluminescence spectra provide insight into the charge distribution among the different nanotubes. For very high charge carrier densities (e.g. by electrolyte-gating) we observe red-shifted trion emission in addition to exciton emission. Furthermore, monochiral s-SWNT films are interesting materials for strong light-matter interaction due to their small Stokes shift and large exciton binding energy. Here, we demonstrate exciton-polariton formation in suitable cavities and emission enhancement in periodic feedback structures.