EN
Paper reports the results of X-ray diffraction, X-ray absorption spectroscopy and the Mössbauer spectroscopy of metal-insulator films sintered in Ar+O atmosphere evidencing the difference in oxidation of FeCoZr nanoparticles embedded into Al_2O_3 and Pb(ZrTi)O_3 matrixes. It is proved that Al_2O_3 matrix with high resistance to oxidation favors the formation of nanoparticles with "metal core-oxide shell" structure, while fully oxidized nanoparticles are observed inside Pb(ZrTi)O_3 matrix.