Temperature effects induced by NIR photo-stimulation within Ist and IInd optical biological windows of seed-mediated multi-shell nanoferrites

Abstract

Different types of ferrite core–shell structures, namely CoFe₂O₄@CoFe₂O₄, CoFe₂O₄@Fe₃O₄, CoFe₂O₄@MnFe₂O₄, and CoFe₂O₄@MnFe₂O₄@ZnFe₂O₄, 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, i.e., temperature, time, and solvent. The contactless conversion of laser light within I^st (808 nm) and II^nd (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.