Gold@Prussian blue analogue core-shell nanoheterostructures: their optical and magnetic properties.

Au@Prussian-Blue Analogue (PBA) shell nanoheterostructures are multifunctional nano-objects combining optical properties (surface plasmon resonance) of the Au core and magnetic properties of the PBA shell. We report in this article a series of new Au core@PBA shell nano-objects with different PBA shells: Au@K/Co/[FeII(CN)6] (2) and Au@K/Ni/[CrIII(CN)6]:[FeII(CN)6] (3) single PBA shell, as well as Au@K/Ni/[FeII(CN)6]@K/Ni/[FeIII(CN)6] (4) double PBA shell and Au@K/Ni/[FeII(CN)6]@K/Ni/[FeIII(CN)6]@K/Ni/[CrIII(CN)6] (5) triple PBA shell systems. The position and intensity of the Au SPR band, as well as the magnetic behaviour of the nanoheterostructures, are strongly affected by the shell composition and its thickness.