NSF Award
2403736
With the support of the Macromolecular, Supramolecular and Nanochemistry (MSN) program in the Division of Chemistry, Professor Guangbin Dong at the University of Chicago is developing efficient and scalable synthetic approaches for preparing atomically precise graphene nanoribbons (GNRs). These nanoribbons are exquisitely thin strips of graphene: a sheet of carbon atoms arranged in a rigid structure that resembles chicken wire. Graphene nanoribbons have emerged as attractive organic materials for potential applications in high speed, lightweight, flexible electronic, and spintronic devices. In this project, physical organic chemistry knowledge will be combined with advanced tools of transition metal catalysis to develop efficient strategies for making these interesting materials. If successful, the research will address a long-standing challenge of preparing narrow zig-zag graphene nanoribbons for studying their physical, electronical, optical, and magnetic properties. The research team will also be actively engaged in the Chicago Pre-College Science & Engineering Program (ChiS&E) to provide early chemistry education to Chicago public middle-school students, the Collegiate Scholars Program to teach high school students, and the Leadership Alliance Summer Research Early Identification Program (SR-EIP) to offer lab research experience to undergraduate students. Integration of the project with these outreach activities has the potential to greatly encourage diverse and students from underrepresented groups to explore careers in science and engineering while learning and actively contributing to research.<br/><br/>The research project will focus on the development of efficient and scalable synthetic approaches towards atomically precise and narrow N=3-5 zigzag graphene nanoribbons (zGNRs). The preparation and fabrication in liquid phase of well-defined pristine zGNRs are very challenging and underdeveloped. To overcome these unmet challenges, stepwise cyclodehydrogenation approaches to access zGNRs from their more stable oxidized or reduced precursor ribbons will be devised. The novel monomer synthesis, on the other hand, will be explored using palladium/norbornene catalysis. Compared to the existing approaches for GNR synthesis, the merits of the new strategies have the potential to be quite significant: (i) monomers will be prepared in a streamlined manner from commercially available starting materials; (ii) the syntheses will be scalable by using in solution polymerization; (iii) air sensitive intermediates will be circumvented, easing the material transfer process; (iv) aryl−aryl cleavage defects are to be minimized by avoiding labile m-xylene-type units. The knowledge gained from this project has the potential to advance the understanding of these graphene-like quasi-one-dimensional polymers, which in turn will further stimulate the development of other new conjugated organic semiconducting materials.<br/><br/>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.
