MRI: Acquisition of a field emission scanning electron microscope to expand characterization capabilities at the University of Iowa

A Field Emission Scanning Electron Microscope (FE-SEM) with added diverse imaging and detection capabilities will be acquired by the University of Iowa (UI). This FE-SEM system will 1) improve the quality and range of data that will be collected and analyzed, 2) increase the speed of data collection and thereby enable more efficient and effective use of research and educational funds, 3) facilitate quantitative evaluation of robust datasets, 4) provide additional opportunities for training STEM students for the 21st Century on a robust, user-friendly analytical tool that can be easily learned with comparatively low training time, 5) provide key support for undergraduate and graduate student research and teaching across a wide spectrum of disciplines, 6) be used regularly by faculty in the Earth & Environmental Sciences Department, as well as researchers in the Chemistry and Anthropology Departments and staff in the Iowa Geological Survey, 7) deliver a new level of micro and nano imaging capability for users from the College of Engineering and Department of Physics and Astronomy, and 8) greatly enhance electron microscopy competencies at UI thereby opening new avenues of research to a wider user base within the university itself and surrounding region.

Placement of the instrument into the new Iowa Materials Analysis, Testing, and Fabrication (MATFab) facility will provide critical staff and infrastructure support for the instrument, researchers at UI, easy access for researchers at UI and from neighboring institutions (Iowa State University, Cornell College) who identified as major users, as well as others who would be occasional users (University of Northern Iowa, Kansas State University, Purdue University). We envisage that this instrument will become a regional facility, attracting users from elsewhere in the Midwest, given its unique capabilities that are not available elsewhere in the region.

Addition of a Field Emission Scanning Electron Microscope (FE-SEM) with automated mineralogy capabilities will expand the scope of Earth Science research and education and transform the materials characterization capabilities of existing facilities available at the University of Iowa. Detailed chemical and textural sample characterization are increasingly critical components of many in-situ microanalytical applications in the Earth and material sciences.

Correct interpretation ultimately rests on understanding the primary context of the material or grains of interest. Establishing this context involves documenting the distribution and spatial relationships of minerals or phases within a sample. Secondary electron (SE) and backscattered electron (BSE) imaging will be combined with automated energy-dispersive X-ray spectroscopy (EDS) analysis for rapid mineral identification and quantitative characterization of mineral abundance, elemental distributions, and textural properties across a broad range of materials.

Cathodoluminescence (CL) imaging capabilities will greatly enhance current research efforts in trace element zoning characterization for petrologic and geochronologic studies. Simultaneous automated collection of all signals will provide cutting edge correlation of mineral distribution and textures and major, minor and trace element distributions. A field emission source will enable maximum signal generation and source longevity for mapping applications while also enabling nanometer scale imaging resolution for characterization of synthetic and natural nanomaterials.

The instrument will be primarily used for applications related to geochronology and petrochronology, structural and metamorphic fabric analysis, igneous petrology, and characterization of sedimentary strata, but other applications will include economic geology, archeology and anthropology, and characterization of environmental surface films, synthesized catalytic materials and optoelectronic semi-conductor devices, as well as engineering applications.

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.