A theoretical study of Ti nanoparticle effect on sodium water reaction: Using ab initio calculation

Abstract

The sodium water reaction (SWR) is a serious impediment to development of sodium fast cooled nuclear reactors. The reaction can be suppressed by suspending 2 at% of 10-nm Ti nanoparticles (NPs) in liquid Na, but the mechanisms by which the Ti NPs suppress the SWR are not known. In this study, ab initio calculation revealed a strong chemical bond with interaction strength 1.65 eV (64.5 kT at 298 K) between Na atoms and the Ti NP surface. We postulate that this interaction with Ti atoms causes a layer of Na atoms to form on the Ti NP surface, and that this layer increases both hydration energy and the activation energy required to initiate SWR. As a result, these interactions suppress the SWR by reducing effective reaction area. (C) 2014 Elsevier B.V. All rights reserved.