1. Department of Physics, Astronomy and Materials Science, Missouri State University, Springfield, Missouri 65897, United States
2. Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
3. GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany
4. University of Arkansas Nano-Bio Materials Characterization Facility, University of Arkansas, Fayetteville, Arkansas 72701, United States