Temperature effects induced by NIR photo-stimulation within I and II optical biological windows of seed-mediated multi-shell nanoferrites.

Different types of ferrite core-shell structures, namely CoFeO@CoFeO, CoFeO@FeO, CoFeO@MnFeO, and CoFeO@MnFeO@ZnFeO, were prepared by the seed-mediated approach. We show that this synthetic methodology offers great and important flexibility in the engineering of multi-shell ferrite nanoparticles which can be further used in various advanced applications. This impressive tool can be used for particle size tuning of homo- and heterostructures through convenient control of the concentration of metal acetylacetonates without the necessity of changing synthetic parameters, , temperature, time, and solvent. The contactless conversion of laser light within I (808 nm) and II (1122 nm) biological optical windows was studied on the fabricated ferrite core-shell materials which showed promising heating effects that can be a basis of their practical exploitation in the biomedical field.