Abstract
In situ investigation of the temperature induced phase transformation, structural and chemical evolution of nanocrystals is important for understanding the structure and stability of nanomaterials. Transmission electron microscopy (TEM), one of the most powerful tools for characterizing nanostructured materials, is essential for the development of nanotechnology. In situ TEM is a technique that allows a direct observation of dynamic properties in nanoscale. Recent development of ultra-high vacuum TEM (UHV-TEM) further enables the investigation on atomic-scale materials systems in a clean environment. The appropriate utilization of the UHV-TEM will be beneficial in studying the fundamental mechanisms of dynamic reactions, formation of transient phase, solid-state amorphization, epitaxial growth, growth kinetics and evolution of defects. In this paper, we present the most recent progress in observing dynamic processes in nanoscale by in situ UHV-TEM. c 2010 Elsevier B.V. All rights reserved.