Spatially Defined Radical-Containing Polymers for Enhanced Charge Transfer

Texas A&M Engineering Experiment Station, College Station TX

Investigators

Abstract

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Drs. Emily Pentzer and Jodie Lutkenhaus from Texas A&M University will advance the fundamental knowledge of how the placement of groups that can transfer electrons (dubbed “redox-active groups”) on polymers and particles impacts their ability to store and produce electrical energy. This will be accomplished by preparing polymers with controlled spacing between redox-active groups, then determining how the structure of these polymers impact their ability to move electrical charges. The advanced knowledge produced through this work may lead to ground breaking advances for energy, electronic, and medical applications, such as enabling organic polymers to replace the metal components of batteries. In addition to the scientific research, undergraduate students, graduate students, and a postdoctoral researcher will be trained to address complex problems and be productive members of a collaborative STEM workforce; educational videos and hands-on demonstrations will be produced and shared; and high school women will be mentored through the US National Academy of Engineering EngineerGirl website. Three different classes materials will be synthesized and used to identify the relationship between structure and electrochemical properties. One organic redox-active group will be used for these studies (2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)), and the knowledge gained should be applicable to other redox-active units. In the first class of materials, the organization of the TEMPO units around a polymer backbone will be varied; in this class, the number of atoms between the TEMPO units will remain the same but their spatial orientation around will be different. In the second class of materials, the spacing between TEMPO units on a polymer backbone will be varied; in this class, the number of atoms between the TEMPO units will be changed. The third class of materials that will be prepared are solid spherical particles that are decorated with either TEMPO groups or short polymer chains that contain TEMPO groups; these decorated particles will be added to the TEMPO-containing polymers. The different structures of the three classes are expected to change how the TEMPO units interact with each other in a solid film, and thus how electrical energy can be stored. The physical and electrochemical properties of the materials will be thoroughly characterized and the work will likely produce knowledge on how material structure correlates to transfer of electrons and ions in polymer-based materials. 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.