| About this Abstract |
| Meeting |
MS&T23: Materials Science & Technology
|
| Symposium
|
Controlled Synthesis, Processing, and Applications of Structural and Functional Nanomaterials
|
| Presentation Title |
Rubbing Powders: Interfacial Radical Formation in Compacted Nanoparticle Ensembles |
| Author(s) |
Oliver Diwald, Thomas Schwab, Aicher Korbinian, Keith McKenna, John Dunlop |
| On-Site Speaker (Planned) |
Oliver Diwald |
| Abstract Scope |
Powder compaction-induced surface chemistry in metal oxide nanocrystal ensembles is important for diverse fields such as cold sintering of ceramics and triboelectrics. Compaction of MgO or BaTiO3 nanoparticle powders with uniaxial pressures that can be achieved by gentle rubbing or pressing (p ≥ 5 MPa) excites energetic electron-hole pairs and generates oxygen radicals at grain interfaces.[1] With electron paramagnetic resonance and density functional theory (DFT) calculations we explored the energetics of charge separation and radical formation that involves ion excitation at grain surfaces and oxygen adsorbed at points of contact.
This study provides for the first time molecular-level information on the pressure-induced separation of charge carriers on metal oxide grains. Since underlying processes can occur prior to the step of sintering, such insights serve as an important for engineering of interfaces in compressed metal oxide nanoparticle powders.
[1] Schwab, T.; et al.; J. Phys. Chem. C 2021, 125, 22239. |