| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Functional Nanomaterials: Functional Low-Dimensional (0D, 1D, 2D) Materials 2022
|
| Presentation Title |
Tuning the Rapid Thermochemical Pretreatment of Alumina-supported Iron Catalyst to Improve Catalytic Lifetime in Chemical Vapor Deposition of Carbon Nanotubes |
| Author(s) |
Golnaz Najaf Tomaraei, Jaegeun Lee, Moataz Abdulhafez, Mostafa Bedewy |
| On-Site Speaker (Planned) |
Golnaz Najaf Tomaraei |
| Abstract Scope |
One problem in chemical vapor deposition (CVD) of carbon nanotubes (CNTs) using oxide-supported metal catalysts is the limited catalytic lifetime. The initial state of catalyst nanoparticles is determined during the formation stage via solid-state thin film dewetting in a reducing environment. Catalyst nanoparticles continue to evolve during CNT growth until deactivation by chemical poisoning, carbon overcoating, or catalyst loss by migration to the surface or underlying layer. These deactivation mechanisms rely on both catalyst formation and CNT growth conditions. Therefore, boosting catalytic lifetime requires optimizing these steps independently. We use a custom-designed multizone, rapid thermal processing CVD reactor to tune the rapid thermochemical pretreatment of alumina-supported iron catalyst, independently from the catalyst activation and CNT growth steps. We show that increasing the catalyst nanoparticle formation temperature to 900 °C in hydrogen results in denser and less porous alumina thin films, postponing deactivation by suppressing catalyst diffusion into the support layer. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nanotechnology, Thin Films and Interfaces, Characterization |