RUI:Development of pi-Conjugated Carboxylic Acids For Use in Self-Assembling Materials

With the support of the Macromolecular, Supramolecular, and Nanochemistry Program in the Division of Chemistry, Prof. Alexander Rupprecht of Saint Bonaventure University will study the self-assembly and properties of single-molecule thick films of rigid organic molecules on metal oxide surfaces, commonly known as self-assembled monolayers (SAMs). Understanding and manipulating the chemistry of a material’s surface is imperative to developing next-generation materials; this work will provide seminal studies and insight into new classes of absorbates that will significantly influence the interfacial properties of metal oxides. A combination of spectroscopic techniques will probe the SAMs ordering and bonding to the surface. In addition to the proposed research objectives, this will be a platform through which student participation in STEM-related activities will be broadened amongst underrepresented populations. Furthermore, undergraduate students will improve their scientific communication and literacy skills by participating in the proposed activities. Currently, the field of self-assembled monolayers is dominated by the use of all-alkyl (long chain, aliphatic) carboxylic and phosphonic acids, resulting in 1) interactions between adsorbates being limited to van der Waal's interactions, 2) disorder caused by flexibility observed in the monolayer tails and, 3) the all-alkyl tails of the monolayers are not conductive. To address these shortcomings, sets of oligo(phenyl), oligo(phenyl-ethylene), and oligo(phenyl-ethylyne) carboxylic acids will be synthesized and used to form self-assembled monolayers. As a result of the molecular structure, these SAMs will exhibit pi-stacking interactions, be highly ordered, and be conductive. The self-assembly, stability, packing, and coordination to the metal oxide surface of these novel adsorbates will be probed using various spectroscopic techniques and microscopy. Furthermore, it is anticipated that the surface properties of these adsorbate-modified surfaces will tune the electrochemical properties of the surface and the surface energy. 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.