Preparation of Chromium doped uranium nitride via Sol-Gel and Carbothermic reduction

Uranium nitride (UN) has been proposed as an accident tolerant fuel due to its enhanced thermal properties compared the standard UO2. However, low oxidation resistance, implementation in water cooled reactors not allowed. A method improve corrosion resistance involves doping with oxide scale forming elements such aluminum or chromium. In this work, UN microspheres were produced by internal gelation followed carbothermic reduction and nitridation. Chromium was added dopant solution produce a homogenous mixture uranium. The ternary phase (U2CrN3) observed for first time Cr-doped via sol-gel reduction. Materials without produced, mechanism of reaction proposed. precipitations also on surface indicating solubility Cr compounds matrix. ICP-MS XRF measurements showed that content is reduced after heating treatments, probably evaporation. Additionally, these results completely soluble aqua regia, unlike material phase.