Reductive dissolution of Fe3O4 facilitated by the Au domain of an Fe3O4/Au hybrid nanocrystal: formation of a nanorattle structure composed of a hollow porous silica nanoshell and entrapped Au nanocrystal

The Fe3O4 grain of a Fe3O4/Au hybrid nanocrystal encapsulated in a silica nanosphere was rapidly and exclusively dissolved through a reductive process facilitated by the attached Au grain, resulting in the formation of a nanorattle structure which has utility as a nanoreactor to template the growth of nanocrystals inside the cavity.