Dynamic Processes in Biology, Chemistry, and Materials Science: Opportunities for UltraFast Transmission Electron Microscopy - Workshop Summary Report

Abstract

This report summarizes a 2011 workshop held at the Environmental Molecular Sciences Laboratory (EMSL) in Richland, Washington, that addressed the potential role of rapid, time-resolved electron microscopy measurements in accelerating the solution of important scientific and technical problems. A series of U.S. Department of Energy (DOE) and National Academy of Science workshops have highlighted the critical role advanced research tools play in addressing scientific challenges relevant to biology, sustainable energy, and technologies that will fuel economic development without degrading our environment. Among the specific capability needs for advancing science and technology are tools that extract more detailed information in realistic environments (in situ or operando) at extreme conditions (pressure and temperature) and as a function of time (dynamic and time-dependent). One of the DOE workshops, "Future Science Needs and Opportunities for Electron Scattering: Next Generation Instrumentation and Beyond," specifically addressed the importance of electron-based characterization methods for a wide range of energy-relevant Grand Scientific Challenges. Boosted by the electron optical advancement in the last decade, a diversity of in situ capabilities already is available in many laboratories. These capabilities enable the investigations of biological and chemical processes in situ with the high spatial and spectroscopic resolution provided by transmission electron microscopy (TEM). The remaining major capability gap is the lack of time resolution. State-of-the-art in situ TEM instrumentation allows time resolution of seconds or milliseconds at best. Present capabilities are far removed from the natural time scale on which processes on a microscopic level occur which is between microseconds (µs) to attoseconds (as).In an effort to address current capability gaps, EMSL, with support from FCSD, the Fundamental & Computational Sciences Directorate at PNNL, organized an "Ultrafast Electron Microscopy Workshop," held June 14-15, 2011, with the primary goal to identify the scientific needs that could be met by creating a facility capable of a strongly improved time resolution with integrated in situ capabilities. The workshop brought together more than 40 leading scientists involved in applying and/or advancing electron microscopy to address important scientific problems of relevance to DOE's research mission. This workshop built on previous workshops 1 and included three breakout sessions identifying scientific challenges in biology, biogeochemistry, catalysis, and materials science-frontier areas of fundamental science that underpin energy and environmental science-that would significantly benefit from ultrafast transmission electron microscopy. In addition, the current status of time-resolved electron microscopy was examined, and the technologies that will enable future advances in spatio-temporal resolution were identified in a fourth breakout session.The major conclusion of the workshop was that significant scientific...

Ultrafast electron diffraction

“…It is also correlated to other dynamical responses of materials involving electronic, magnetic, and other degrees of freedom, which account for most of materials' functionalities. [1] A through understanding of structural dynamics and its complex correlation to other degrees of freedom requires synergetic use of multiple techniques to provide complementary views. Ultrafast electron diffraction (UED) technique addresses such request by providing real-time and atomic-level view of structural dynamics.…”