| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Nanomaterials | Wednesday Sessions |
| Session NM-WeM |
| Session: | Nanocharacterization |
| Presenter: | Michele Conroy, Pacific Northwest National Laboratory, USA |
| Authors: | M. Conroy, Pacific Northwest National Laboratory, USA J. Soltis, Pacific Northwest National Laboratory, USA S. Chatterjee, Pacific Northwest National Laboratory, USA E. Buck, Pacific Northwest National Laboratory, USA |
| Correspondent: | Click to Email |
Aluminum oxyhydroxide (boehmite) nanoparticles are used for a wide variety of applications including catalysis and adsorption. It has been shown that boehmite nanoparticles with 010 plane as the largest exposed surface area have increased catalysis and adsorption rate, due to the relatively high OH density of this plane. Additionally synthesizing these nanoparticles in a hierarchical structures instead as mono-dispersed, has been reported to increase the reactivity even further. In this study we utilize cryo-transmission electron microscopy (TEM) and in-situ liquid TEM to achieve fundamental insights into the mechanisms of nanoparticle aggregation and reactivity. Although there is a lot of theoretical debate around the preferential interacting zones of AlOOH crystalline nanoparticles in solution, there has been no experimental confirmation to date. Our initial results show that the particles aggregate along a preferred crystal orientation (the main flat (010)), irrespective of pH and solution content, forming large stacked agglomerates and decreasing the exposed surface area.
Aluminum oxide nanoparticles formed by the dehydration of boehmite are also widely used in industrial catalysis including petrochemical, chemical, and automotive due to their stability at high temperatures. Although the shape of the nanoparticle during the thermal treatment of boehmite remains the same the terminating planes of course change with the removal of water. This enabled us to study any change in the aggregation due to the terminating chemistry without the shape of the nanoparticle itself being a possible variable.