Removing radioactive material from water is an incredibly complicated task thanks to the fact that there is no easy way to separate the two. Future disaster recovery crews could have an easier time of it, however, thanks to flakes of graphene oxide. Adding the flakes to contaminated water causes them to clump up into solids with the radioactive material trapped within. The clumps can then be scooped up easily.
The solids are still radioactive and must be treated as such, but they can then be used to re-capture the radioactive material. After burning the graphene oxide, a cake of radioactive material is left and can then be re-used for another application. The graphene oxide flakes are inexpensive and biodegradable in addition to trapping radioactive ions very effectively, making this solution ideal for cleaning up large-scale radioactive disasters.