Expanding the supramolecular chemistry of carbon nanohoops

University Of Oregon Eugene, Eugene OR

Investigators

Abstract

With support from the Macromolecular, Supramolecular, and Nanochemistry (MSN) Program of the Division of Chemistry, Professor Ramesh Jasti at the University of Oregon is developing general methods to use nanohoop molecules as building blocks to self-assemble into precise nanoscale materials with controlled shape and function. Two forms of structures are envisioned: interlocked structures and ring-in-ring structures. Novel synthetic approaches are to be explored to achieve these objectives. The desired products are expected to have unique size-dependent optoelectronic properties and shape persistent pores. The products being targeted are of potential use in broad ranging fields from gas adsorption, filtration and mass transport to molecular electronics, switching, and sensing. Students involved in the project will be trained in an interdisciplinary environment and acquire experience in organic synthesis, supramolecular chemistry, and nanoscience. A partnership with the University of Oregon Summer Science Program provides hands-on science experience to groups of students who have been underserved in the state of Oregon. The assembly of molecular building blocks into precise nanoscale materials with novel function is a grand challenge at the nexus of materials science, supramolecular chemistry, and synthesis. While synthetic approaches for the preparation of nanohoops have been developed in the last decade, the self-assembly of these nanohoops into nanoscale materials with controlled shape and function is relatively unexplored. In the first aim of the project, the Jasti group will explore nitrogen-doped nanohoop analogues and metal-coordination strategies to prepare catenane structures, which would represent simple versions of molecular machines. The Jasti group will probe these new catenane structures for novel properties such as optoelectronic communication through the mechanical bond or ultra-low friction motion on the nanoscale. In the second aim of this project, the Jasti research team plans to use the hydrophobic effect to drive the formation of ring-in-ring nanohoop complexes. These structures are molecular analogues to double-walled carbon nanotubes and are predicted to have unique optoelectronic properties and dynamics due to the supramolecular assembly of the components. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.