Nanocrystal Transformers
Materials Science Division researchers have, for the first time, directly observed structural transformations in semiconductor nanocrystals. Studying structural transformations in ordered materials is of great interest in many applications, from light harvesting and materials manufacture to energy storage, in which such transformations affect device performance.Using TEAM 0.5, one of the world's most powerful transmission electron microscopes, the group observed structural fluctuations in a copper sulfide nanocrystal as it transitioned between two solid-state phases. Phase transitions in nanoscale materials occur with changes in temperature or pressure, resulting in a change in materials properties.
By viewing these transformations, the team revealed atomic pathways of phase nucleation, propagation, and pinning of structural domains through defects. TEAM 0.5 enabled rapid sample imaging with single atom sensitivity, providing an opportunity to study structural transformation dynamics as they occur. Such structural changes hold important implications for numerous phenomena, including ion transport within electrodes during charging and discharging of batteries.
---
