Preparation of Epitaxial Uranium Dicarbide Thin Films by Polymer-Assisted Deposition

High quality epitaxial thin films of cubic UC2 were synthesized using a solution based technique. The films were characterized using XRD, UPS, Raman, and resistivity. The substrate lattice is yttrium stabilized zirconia and serves to stabilize the high temperature cubic phaseof UC2 (>1765 °C) at room temperature. The resistivity and UPS data indicate that UC2 has relatively low electrical conductivity consistent with HSE hybrid DFT calculations showing a narrow band gap. In situ XRD measurements show that the UC2 films oxidize to U3O8 above 200 °C.