KY EPSCoR: Transforming Kentucky's New Economy with EPSCoR: Advanced Materials XPS System Acquisition

This scope account request (under prime KY NSF EPSCoR account 3048108526) is a part of the KY NSF EPSCoR Advanced Materials initiative to improve Kentucky’s research infrastructure via acquisition of an XPS system to allow for advanced materials characterization as described at an on-campus seminar (summarized below). The surface chemistry of all materials determines their interaction with other substances in the environment and thus affects important material properties such as adhesion strength, catalytic activity, corrosion resistance, susceptibility to oxidation, and other critical chemical and physical characteristics. Knowledge of the surface chemistry is therefore crucial to the successful production and operation of innumerable advanced materials such as coatings, ceramics, composites, metals, polymers, and thin films, among others. Highly developed surface sensitive techniques are required to properly characterize the surfaces of advanced materials and specialized products. X-ray Photoelectron Spectroscopy (XPS) is a qualitative and quantitative chemical analysis technique that probes only the outer few nanometers of the surface, thus enabling researchers to better understand what surface compositional properties influence optimum material performance. XPS, angle-resolved XPS (ARXPS), XPS imaging and mapping, and XPS sputter depth profiling are methods that are ideally suited to the determination of the surface chemistry and the way in which that chemistry changes from the surface and near-surface regions into the bulk of the material. XPS is the only analytical technique providing quantitative elemental and chemical state information with extremely high surface sensitivity, making XPS the technique of choice for comprehensively characterizing material surfaces and interfaces. Recently developed argon cluster ion sources provide soft depth profiling capabilities, which allows the in-depth characterization of polymers and other organic materials that cannot be readily profiled using traditional monatomic argon ion sources. XPS spectroscopic imaging and mapping, in which spectral data are acquired with some degree of lateral resolution, allows the identification of both spatial and chemical variations in materials. The expansive data sets that result from spectroscopic imaging and mapping experiments must be treated with powerful software algorithms, in order to extract high levels of chemical information with a minimum of acquisition time. This presentation will discuss XPS solutions to structural and chemical problems regarding a wide variety of advanced materials. Example materials highlighting the unique surface characterization capabilities of XPS will include: 1) supported transition metal catalysts; 2) multi-layer inorganic thin film structures on glass, medical implant devices, and solar cells; and 3) functional biological, organic, and polymeric thin films.