On the durability of Pt coated Ti electrodes for the electro-oxidative dissolution of spent nuclear fuels

Abstract

The main objective of this study is to assess the long-term performance of Pt nanoparticle coated anodised Ti coupons which are used for electrochemical dissolution of spent mixed-oxide nuclear fuels during reprocessing. In this work, electrodes were exposed to a simulated dissolver solution containing a representative fraction of low-activity actinides and fission products in 11.5 N nitric acid in a mock-up of the service dissolver vessel. Platinum nanoparticles were coated onto anodised titanium coupons through a seed-mediated hydrothermal method. The coated coupons were then exposed in the simulated dissolver solution for about 1185 h at 110°C. Morphological and compositional analyses confirmed the presence of metallic Pt nanoparticles on the electrode surface with some localised cracking. The electrochemically active surface area of the Pt-nanoparticle coated anodised titanium coupon after exposure was found to be twice that of polycrystalline platinum thus establishing the durability and efficiency of the coating on the electrode.