CAREER: Standing, Lying, and Sitting: Restructuring Intermolecular Forces in Molecular Monolayers and Freshman Chemistry

Purdue University, West Lafayette IN

Investigators

Abstract

Professor Shelley Claridge of Purdue University is supported through a CAREER award by the Supramolecular, Macromolecular and Nanochemistry Program of the Chemistry Division to develop bioinspired surface chemistry that tailors electronic properties and solubility of technologically important layered materials. Graphene and other layered materials have the potential to improve applications ranging from high-efficiency solar cells to precision biosensors. Controlling surface chemistry represents a useful means of affecting properties such as conductivity and solubility to help reach these aims. However, in practice this control has been difficult to achieve. Professor Claridge's group takes a bioinspired approach to solving both problems using one of nature's chosen building blocks for controlling interface chemistry: fat molecules (lipids). The educational component of this program uses campus dining facilities as context-rich learning environments for first-year general chemistry students and the campus community. The proposed research uses an unconventional self-assembly strategy based on lipids reoriented into a 'sitting' geometry. This strategy provides precise spatial control over layered material surface chemistry from sub-nanometer to micron scales, enabling nanoscale patterning, device and biological applications. The project establishes a framework for designing new amphiphilic surface chemistries based on independent modifications of each piece of the amphiphile. The new surface chemistry simultaneously controls ligand-substrate electronic coupling and ligand-solvent interactions important for material solubility and processability. For semiconductor nanocrystals, rigorous control of ligand chemistry has proven to be a key enabler in technological applications; establishing similar control over layered material surface chemistry is expected to provide similar benefits. The educational component of the project makes creative use of campus dining facilities as a shared learning environment for students to improve their understanding of intermolecular forces important in proteins, lipids, and carbohydrates, and assesses their understanding using a published instrument based on structure-drawing problems.