Symposium S.CT03 : Expanding the Frontiers of Actinide Materials Science Through Experiment and Theory
Rachel Eloirdi, JRC Karlsruhe
The JRC Surface Science Labstation. A Unique Set-Up to Investigate Actinides in Support of Nuclear Safety and Non-Power Application of Nuclear Materials
Written by Emma Perry
The Labstation has been specifically designed to produce and characterize actinide thin films. Here you can prepare high purity thin films used in a controlled atmosphere. The labstation then connects to characterization modules for x-ray photoelectron spectroscopy, grazing incidence x-ray diffraction, atomic force microscopy, high-resolution electron energy loss spectroscopy, and temperature programmed desorption. Unsurprisingly this highly versatile machine has been put to use in a number of cutting-edge case studies.
In the development of sodium cooled nuclear reactor technologies it is important to predict what will happen if sodium comes into contact with uranium. So, in the preparation module, UO3 and Na were deposited onto a thin film. Using the x-ray absorption spectroscopy module, it was found that at room temperature sodium does not reduce uranium. Then, during heating, a mixed state of U(IV) and U(V) was observed until 973 K when the sodium stabilized uranium in the pentavalent state.
To observe the effect of water radiolysis products on UO2, U(IV) thin film were produced and exposed to O2 plasma. Amorphous U(VI) formed. When exposed to H2O plasma, a new unknown crystalline surface was observed.
The labstation has also been used to observe the bandgap of ThF4 deposited on Au substrate in order to ascertain its viability as an optical nuclear clock.