MRI: Acquisition of an Electron Energy Loss Imaging Filter for Real-time Microchemical Dynamics and Chemical Tomography

点击翻译按钮获取中文摘要

Technical Abstract:This proposal seeks to acquire an electron energy loss imaging filter for installation on an existing multi-user 200 kV transmission electron microscope (TEM), managed by the Penn State Materials Characterization Laboratory. With recent institutional investment, this TEM has been upgraded to facilitate in-situ dynamical studies of material structure at the nanometer length scale as a function of temperature, applied electrical bias or applied stress. The imaging filter will allow for parallel, real-time mapping of chemical transport such that chemical dynamics and their interactions with nano- and micro-structural features can be studied. Microchemistry will be monitored real-time during phase-transformation, diffusional and electrochemical studies of materials. Another class of experiments that the energy filter will enable is energy-filtered diffraction, such that we can perform quantitative radial distribution function analysis on non-crystalline materials and quantitative strain analysis on strain-engineered thin films. The experiments enabled by the energy filter will have broad institutional impact and will significantly impact several NSF-funded centers at Penn State including the MRSEC Center for Nanoscale Science, the I/UCRC Center for Dielectric Studies and the I/UCRC Particulate Materials Center. In addition, through summer outreach programs with which the PI is affiliated, e.g. Girls Utilizing Technology and Science, Science Educator Workshops, and Research Experiences for Undergraduates, we will utilize the energy filter capabilities to provide visual insight into nanomaterial chemistry to high school students, undergraduates and traditionally underrepresented groups.Non Technical Abstract:Often, the macroscopic properties of materials (e.g., mechanical, thermal, and electrical) are governed by structural and chemical inhomogeneites in the materials at the micrometer and nanometer scale. One invaluable technique for studying structure at the nanometer scale is the transmission electron microscope (TEM). This proposal seeks to acquire a spectrometer to attach onto the TEM, specifically and electron energy loss imaging filter, which will allow for simultaneous chemical characterization. In fact, chemical maps at the nanometer length scale can be formed and recorded real time as the material is subjected to thermal, electrical or mechanical stresses. The addition of this spectrometer will significantly enhance the research, educational and outreach missions of Penn State. The new imaging filter will be incorporated into existing characterization and nanotechnology coursework, and a new hands-on, graduate-level laboratory course will be created on energy-filtered imaging. Furthermore, having access to the imaging filter will promote research with wide ranging societal benefits through technological sectors such as healthcare, microelectronics, manufacturing and energy.