MSE Seminar: Jane Howe

"Visualization of Change of Lunar Soils via Simultaneous SE/TE Imaging During In Situ Heating"

Monday, Feb. 20, 2017
2-2:50 p.m., Harshbarger 206

Abstract:

Our ability to image surface and bulk features of materials plays an important role in the field of nanoscaled materials research. Even more desirable is the capability to simultaneously image morphological and structural changes that occur on the surface and within the bulk of a material with additional stimuli, such as during in situ heating, in situ oxidation, or under tensile stress.

In this presentation, Jane Howe will give an example of using electron microscopy for solving cosmochemistry problem via in situ simultaneous SE/TE imaging. Her team carried out the first dynamic, in situ heating of lunar soils to simulate micrometeorite impacts on the lunar surface. Iron nanoparticles form as a result of the heating in these soil samples, and electron energy-loss spectroscopy measurements suggested that the iron nanoparticles are composed entirely of Fe0, indicating that this simulation accurately mimics micrometeorite space-weathering processes occurring on airless body surfaces. In addition to iron nanoparticles, vesicles also formed on the surface of the lunar soil. Several soil grains were subjected to repeated rapid thermal shocks, and the measured size distribution and number of iron nanoparticles evolved with each subsequent heating event. These results provide insight into the formation and growth mechanisms for iron nanoparticles in space-weathered soils. Moreover, this study establishes a new methodology for materials science and lunar and planetary research.

Biography:

Jane Howe is a senior applications scientist with Hitachi High-Technologies America Inc. She is also a visiting scientist with University of Arizona. Howe received her PhD in ceramic science from Alfred University in 2001. Prior to joining the Hitachi group, Howe worked in the microscopy group of Oak Ridge National Laboratory for nine years as a staff scientist and principal investigator.

Jane Howe has fifteen years of experience in electron microscopy of energy materials. She has over 90 publications on peer-reviewed journals and holds seven U.S. patents. She won two R&D 100 Awards in research and development of the lithium battery materials. Howe's research interest is in solving materials problems via in situ and correlative microscopy techniques.

University of Arizona College of Engineering