Figure 1.

Structure and magnetic properties of Fe₃O₄@Dex and Fe₃O₄@aC: XRD patterns of samples (a) with marked Miller indices of the magnetite spinel phase; comparison of FTIR spectra of Fe₃O₄@Dex (b) and Fe₃O₄@aC (c) with spectra of pure organic modifiers; deconvolution of XPS spectra of Fe 2p, O 1s, and C 1s core lines obtained for Fe₃O₄@Dex (d) and Fe₃O₄@aC (e); and Mössbauer spectra of Fe₃O₄@Dex (f) and Fe₃O₄@aC (g) with fitted curves (the dots, black solid lines, pink and blue represent experimental data, fitted curves, hyperfine magnetic distribution and doublets, respectively). Insets show the recorded VSM curves; size-distribution histograms with cumulative curves plotted for Fe₃O₄@Dex (h) and Fe₃O₄@aC (i) and TEM images of Fe₃O₄@Dex (j–l) and Fe₃O₄@aC (m–o) nanoparticles in STEM (j, m) and HRTEM (k, l, n and o) modes; insets show the FFTs from the green and blue marked areas (o).