Semiconducting carbon nanotube based electronics and photovoltaics

Recent discoveries in achieving highly monodisperse semiconducting carbon nanotubes without problematic metallic nanotubes and advances in depositing these nanotubes into useful, organized arrays and assemblies on substrates have created new opportunities for studying the physics of these one-dimensional conductors and for applying them in electronics and photonics technologies. Here, I will talk about three related topics alone these lines:

1. We show that poly(fluorene) derivatives are some of the strongest nanotube differentiators that have ever been discovered, eliminating metallic nanotubes to less than 1 part per 5000.
2. We have recently pioneered a scalable approach for depositing aligned arrays of these ultrahigh purity semiconducting nanotubes called floating evaporative self-assembly (FESA) that has allowed us to create the highest performance carbon nanotube field effect transistors (FETs) ever demonstrated, using on-conductance and on/off ratio as key metrics.
3. We have discovered how to efficiently harvest photons from thin films of these highly semiconducting nanotubes by driving the dissociation of photogenerated excitons using donor/acceptor heterojunctions. The efficiency of these devices is determined in particular by the flow of energy in these films. This flow of energy occurs across a complex energy landscape that we have temporally resolved and understood using a particularly broadband form of two-dimensional white light ultrafast spectroscopy.