About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Grain Boundaries, Interfaces, and Surfaces: Fundamental Structure-Property-Performance Relationships
|
| Presentation Title |
Evolution of Metal Nanoparticles at Solid–Gas and Solid–Solid Interfaces: Segregation Reactions in Ceramic Matrices |
| Author(s) |
Simone Mascotto, Benjamin Rudolph |
| On-Site Speaker (Planned) |
Simone Mascotto |
| Abstract Scope |
Metal exsolution — forming nanoparticles via segregation from ceramic matrices — has recently emerged as a sustainable strategy for designing efficient heterogeneous catalysts. Typically, metal nanoparticles evolve from doped, defect-rich perovskite oxides under high-temperature reducing conditions. In sintered ceramics, they can also form internally, without direct gas contact.
This study investigates the evolution of nickel nanoparticles at solid-gas (exoparticles) and solid-solid (endoparticles) interfaces in titanate perovskites with 6–40 at% Ni. Exsolution began rapidly, producing ~14 nm exoparticles within 30 minutes. Lower Ni content yielded fewer but larger particles, while higher levels promoted denser, smaller ones due to enhanced nucleation. Small-angle X-ray scattering revealed ~10–12 nm endoparticles forming after 5 hours, which grew and agglomerated despite spatial confinement. Increasing Ni content led to less size variation during growth. Cross-sectional SEM confirmed distinct morphological evolution and host matrix reconstruction, emphasizing the role of defect chemistry and interface dynamics in the exsolution process. |