M Gharagozlou - Department of Nanomaterials and Nanotechnology, Institute for Color Science and Technology, Tehran, Iran
R Jafari - Department of Color Physics, Institute for Color Science and Technology, Tehran, Iran

In this research, the colorimetric attributes of nanocomposites of Ni-Fe spinels and Co-Fe spinels dispersedin silica matrix are compared. In this way, the same percentages of Ni-Fe spinel nanoparticles and nano-sized Co-Fespinels are embedded in amorphous component. Then, the colorimetric attributes of nanocomposites are calculated basedon their measured reflectance spectra over the visible wavelengths. Results show that in comparison to thenanocomposites of Ni-Fe spinels, the CoFe2O4/SiO2 nanocomposites are more neutral and appear darker. The smoothreflectance spectra of CoFe2O4/SiO2 nanocomposites over the visible spectrum explain its colorimetric behaviour ratherthan nanocomposites of Ni-Fe spinels.TEM observations indicate that the uniformly dispersed, well-crystallized and almostspherical nanoparticles were homogeneously embedded in the silica network.

Nanocomposites, Co-Fe spinels, Ni-Fe spinels, Silica, Colorimetric property