Quantitative structural characterization and property measurements of materials by in situ electron microscopy

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The long-term objective of the research program is to carry out quantitative structural characterization and property measurements of materials during their exposure to relevant and realistic stimuli or environments, and their real-time evolution during processing and operation at nano and sub-nanometer length scales. The short-term objective is to build a liquid-cell electron and correlative microscopy platform that allows the study of how materials function in liquid environments. We will devote a portion of the program towards the understanding of electron-beam effects in aqueous solutions with multiple species, as well as electron beam interactions with nonpolar solutions and ionic liquids. Based upon the new knowledge gain from the fundamental studies of the beam effects, we are striving to explore new frontiers of liquid cell electron microscopy research with improved techniques in several technological areas including: i) catalysis and photochemistry; ii) corrosion and cavitation; iii) environmental remediation and water treatment; and iv) and identifying extraterrestrial amino acids in the carbon-rich meteorites and asteroids. Transmission electron microscopy (TEM) offers structural and compositional information of materials at the atomic level. TEM is conventionally carried out on a thin, solid sample in high vacuum. In order to study materials immersed in water and other liquids, we propose an interdisciplinary, “lab-in-the-gap” approach. Specifically, using microelectromechanical systems (MEMS) technology with a high level of miniaturization, research will be conducted in fully integrated, closed liquid cell sample holders that enable the study of materials immersed in liquid, with possible additional stimuli such as optical or electrical influence, heat or gas, and simultaneously acquire multiple responses and signals in situ. The CFI-funded Ontario Centre for the Characterisation of Advanced Materials at the University of Toronto includes an environmental TEM and a high-resolution scanning electron microscope that provide the platforms for the proposed Discovery program. Electron microcopy is rapidly evolving from an observational science to an in situ laboratory platform for advancing many fronts of science and engineering research. Liquid cell electron microscopy is one of the areas that is experiencing revolutionary growth. Preliminary data from our prototype liquid cell suggest that we on the right track for making important discoveries in a number of technological sectors. HQP will be directly involved in the design of the liquid microscopy experiments and the operation of the liquid cell holder. They will gain first-hand experience to work with fundamental research coupled with applied interdisciplinary projects to solve critical problems in the fields of materials synthesis, space science, alternative energy resources, and beyond.