In situ TEM Holder for Investigating the Real-time Behaviors of Nanomaterials in the Native Working Environment

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Since the earliest days of transmission electron microscopy (TEM), it has been adapted to track dynamic processes caused by one or more external stimuli by sequentially recording sets of images. In an ideal in situ TEM experiment, the controlled deliberate stimulus applied on the sample (input) and the consequent change in structure and physical properties (output) should be recorded simultaneously to understand the correlation. Compared to the ex situ TEM experiments, the in situ experiment provides a continuous view of a process, which otherwise has to be simulated through numerous ex situ experiments. In situ TEM is also good at capturing transient phenomena which are nearly impossible for ex situ experiments. ******For instance, Dr. Zhi Li investigated the in situ sodiation processes of Sb thin film anode using the TEM facility located at Sandia National Lab and observed the time-dependent buckling and localized separation of the sodiated films from current collectors, indicating that the Na intercalation-induced stress is slowly relaxed in a time scale of days (Nano Lett., 2015,15, 6339). If the experiments were carried out ex situ without continuously observing the same thin-film upon sodiation, the buckling phenomena could be easily misidentified as pristine artifacts in the thin-film. However, the behavior of nanomaterials is strongly affected by working environments because a large proportion of atoms in nanomaterials are located at the surface and interact with environments. Unfortunately, no real batteries are designed to be operated in the environment similar to the high-vacuum in a TEM chamber, which limits the practical impact of our research findings. In fact, this limitation applies to most of the in situ TEM work. ******The recent advances in in situ TEM system based on MEMS chips provides a perfect solution by creating a miniature cell inside the TEM and provide the required liquid or gaseous environment. Herein, three researchers from the Department of Chemical and Materials Engineering at the University of Alberta in collaboration with nanoFAB, request partial finance support through the RTI program for the purchase of an in-situ TEM holder system to support several on-going NSERC research projects. The requested equipment will be installed on an advanced aberration-corrected S/TEM with a cold field-emission gun as an electron source for the best results. This integrated system will significantly speed up our efforts in developing long-lasting batteries to store the green electricity produced in Canada, fabricating robust catalysts for the oil sands industry in Alberta, and understanding the true behaviors of bionanomaterials (e.g., nanocellulose) which are critical for the forest industry in Canada. **