1. Atomistic and experimental study on thermal conductivity of bulk and porous cerium dioxide.
- Author
-
Malakkal L, Prasad A, Oladimeji D, Jossou E, Ranasinghe J, Szpunar B, Bichler L, and Szpunar J
- Abstract
Cerium dioxide (CeO
2 ) is a surrogate material for traditional nuclear fuels and an essential material for a wide variety of industrial applications both in its bulk and nanometer length scale. Despite this fact, the underlying physics of thermal conductivity (kL ), a crucial design parameter in industrial applications, has not received enough attention. In this article, a systematic investigation of the phonon transport properties was performed using ab initio calculations unified with the Boltzmann transport equation. An extensive examination of the phonon mode contribution, available three-phonon scattering phase space, mode Grüneisen parameter and mean free path (MFP) distributions were also conducted. To further augment theoretical predictions of the kL , measurements were made on specimens prepared by spark plasma sintering using the laser flash technique. Since the sample porosity plays a vital role in the value of measured kL , the effect of porosity on kL by molecular dynamics (MD) simulations were investigated. Finally, we also determined the nanostructuring effect on the thermal properties of CeO2 . Since CeO2 films find application in various industries, the dependence of thickness on the in-plane and cross-plane kL for an infinite CeO2 thin film was also reported.- Published
- 2019
- Full Text
- View/download PDF