PNNL

Abstract

This work explores the use of Ni0 foam scaffolds for Cu0 electroplating from aqueous CuSO4 solutions under different conditions to achieve a range of Cu0 layer thicknesses (ranging from 4.89 ± 1.05 µm – 57.32 ± 3.95 µm) for use as sorbents for iodine for electroplating conditions of 900 A·m-2 current densities for coating times of 15-180 min. The thickest coatings resulted in Cu0-plated Ni0 foams with > 89 mass% Cu0 in the final product. Iodine capture experiments showed very high Cu0 utilizations of 91.9–97.3 mass% at iodine loadings of 839–1774 mg·g-1 through the formation of CuI (marshite; space group F-43m). No evidence was found of iodine reactions taking place with the Ni scaffold, so it remained in iodine-loaded Cu-electroplated Ni foams as structural support to provide mechanical rigidity to the foams during the iodine loading process. Hot pressing of these materials can be used to create a CuI/Ni ceramic metal composite waste form for disposal as demonstrated with spark plasma sintering within this paper.