Initial oxidation of U3Si2 studied by in-situ XPS analysis

Abstract U3Si2 attracted much attention as candidate nuclear fuel for some favorable properties such as higher uranium density and thermal conductivity than that of UO2. Until now, the oxidation and hydrolysis mechanism of U3Si2 have not been fully explained. In this paper, we fabricated U3Si2 by arc-melting method and characterized surface morphology and structure by SEM and XRD, respectively. The initial oxidation process of U3Si2 was studied by in-situ XPS analysis. The results showed that the oxidized product of U3Si2 were firstly uranium oxides and then uranium silicate. By XPS peak fitting process, the percentage of oxides were obtained and showed that the oxides percentage increased roughly obeyed the exponential law.