Figure 5
TEM images (a) and T 2 property measurement (b) of the SiO 2 -coated MNPs. The TEM images show that the particles consisted of core CoFe2O4 nanoparticles and a SiO2 coating with a shell thickness of approximately 25 nm, providing a total particle diameter of 70.8 ± 4.3 nm (note the inset for the particle shape in detail). The measured r2 was 130 ± 2 mM−1s−1, which was 27% smaller than that of the MNP group C core alone.