With this award from the Major Research Instrumentation (MRI) program, Svetlana Mitrovski and colleagues Kraig Wheeler, Thomas M. Over and Jie Zou from Eastern Illinois University will acquire a scanning probe microscope. The instrument will enhance research in a number of areas including studies of electrochemical oxygen reduction reaction based on conductive metal oxides; thermal conduction in semiconductor nanostructures; forces between soil particles in support of wind erosion prediction; heteroepitaxial crystal growth of quasiracemates; characterization of spider silks; and interactions between stationary and mobile phases in chromatographic separations.
A scanning probe microscope provides an image of a surface by moving a microscopic probe tip across the material under investigation. After a series of scans in the x-y directions, the image produced provides information on the nature of the surface and substances adhered to it. It is a powerful modern technique in chemistry, physics, biology, materials and geosciences research. The instrument will be used by undergraduates in their research projects and in laboratory courses in several departments at Eastern Illinois University.
The operation of alternative energy devices is critically dependent on how effectively electrical charge can be transported through or stored within the materials of which they are constructed. These materials are often semiconductors and/or conductive polymers in which electrical current (all or in part) is produced by directional motion of ions. Ion transport, on the other hand, can result in the formation of depletion layers and composition gradients that can, in turn, act as driving forces for a number of unexpected phenomena within these materials. We studied the behavior of single crystal perovskite-type oxides under wet electrochemical conditions - ones that would likely be found in batteries and fuel cells - and found that dramatic changes are elicited by the exposure of single crystal perovskite-type electrodes to operational conditions. These changes manifest themselves in the form of phase segregation and exsolution of crystalline particles in regions of the electrode that are not directly exposed to operating conditions (i.e. liquid electrolyte and electrochemical potential). We highlight several outcomes that resulted as a direct consequence of obtaining this grant. First, we were able to follow the growth of these particles and correlate their growth with the electrochemical conditions under which the perovskite electrode operated. Second, we were able to determine their crystal structure and chemical composition. In doing so, we established a working relationship with the scientist at the Frederick-Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign. Two graduate students developed Master's theses that incorporated data from the NSF-funded instrument and one graduate student is in the process of doing so. At least three undergraduate students - all from different departments including chemistry, physics and geology - participated in depth in this research. It is the experience they gained using the new instrument that helped them find rewarding employment and/or enter into prestigeous graduate schools around the nation. Third, the instrument acquired by this grant significantly aided in recruiting new faculty in the area of materials research - especially that related to alternative energy and is expected to significantly help in recruiting graduate students entering the new Masters program in Sustainability at Eastern Illinois University. For two of the six faculty who were assistant professors at the time of application, this was their first NSF grant and one that helped advance their careers towards obtaining tenure.
