Probing and manipulating the photophysics of new semiconducting carbon nanotube films
Abstract
Conventional semiconductors are macroscopic materials in which charges and energy diffuse in 3 dimensions. In contrast, semiconducting carbon nanotubes transport charges and energy, in the form of excitons, in 1 dimension. This transport is unique because it occurs directionally – along the length of the tubes – and quickly – at rates thousands of times faster than other carbon materials such as conducting polymers. Carbon nanotubes are also extremely strong optical absorbers, chemically stable, and solution processable, which are qualifying characteristics for future applications in optoelectronics. Recent efforts have made it possible to condense semiconducting carbon nanotubes into mesoscale films. Understanding the photophysics of these films and learning to how manipulate them to route energy flow in specific directions could lead to new designs of next generation phototransistors, photodetectors, and photovoltaics. Over the last few years, we made the first measurements of energy transfer in prototype nanotube films with a 2D White Light spectrometer that we invented for the purpose, laying the foundation for much of what is known about their novel photophysics. The film properties lie in between bulk semiconductors and isolated nanotubes, depending on how the film is constructed. In this proposal, we outline experiments to precisely test the nature of the mechanisms for energy transfer; use our newfound knowledge to begin manipulating energy flow; and develop new ultrafast 2D imaging methods to spatially resolve exciton diffusion. These efforts will build a foundational understanding of the photophysics displayed by these new materials, result in new optical technologies for precisely probing energy transfer, and put in place the materials science for new device architectures with applications ranging from surveillance to medical imaging.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- FA95501910093
Entities
People
- Martin T. Zanni
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Wisconsin System