We are working to develop a real-time understanding of the mechanistic steps taken during crystalline growth or transformation via a combination of complementary approaches which incorporate (1) knowledge gained from nanostructure syntheses we perform in the lab, with (2) in situ observations of key transformations implemented in real-time using ultra-high resolution transmission electron microscopy (TEM). Our in situ experiments include directly performing synthetic steps in the TEM, as well as determining the structural phase transformations of materials under post-synthetic processing conditions. Further, based on an unexpected observation made during one of these in situ measurements, we have developed a new approach to directly synthesize arrays of crystallographically well-defined nanoscale interfaces. Several examples will be presented to illustrate our approach, including: the real-time observation of the solid-state reaction of an individual nanowire; a post-synthetic structural phase transformation within an individual nanorod; and finally, the creation of new nanostructured architectures using liquid metal nanodroplets.
Beth S. Guiton is an Assistant Professor in the Department of Chemistry at the University of Kentucky (UK). After earning a B.A. in Physical Natural Sciences, and an M.Sci. in Chemistry from the University of Cambridge (United Kingdom), she earned an A.M. in Chemistry from Harvard University where she developed the first synthesis for vanadium dioxide nanowires, and a Ph.D. in Materials Science and Engineering from the University of Pennsylvania, using high resolution microscopy to investigate solid-state nanoscale materials, such as spontaneously-forming nanochessboard structures. After graduating, she was a Eugene P. Wigner Fellow at Oak Ridge National Laboratory, where she worked on high-resolution spectroscopic methods which included mapping the spatial distribution of localized surface plasmon modes. Guiton began her faculty appointment at UK in 2010 establishing a research program combining her interdisciplinary interests, using microscopy to address fundamental questions of solid-state and materials chemistry. Her group has employed local probe techniques, such as in situ heating in the transmission electron microscope to address questions regarding synthetic mechanisms during the creation of nanomaterials, and the precise positions of atoms and interfaces as they relate to material properties. While at UK, Guiton has also received a number of accolades which include the 2015 UK College of Arts & Sciences Undergraduate Research Mentoring award, a 2014 Teacher who Made a Difference award, a 2015 NSF Early CAREER Award, and recently being named an Emerging Investigator in Materials Science by Materials Research Express.