Solid state synthesis and characterization of ferromagnetic nanocomposite Fe–In2O3 thin films

Abstract

We have successfully synthesized ferromagnetic Fe–In2O3 nanocomposite thin films for the first time using the thermite reaction Fe2O3+In=In2O3+Fe. The initial In/Fe2O3 bilayers were obtained by the deposition of In layers on α-Fe2O3 films. The reaction occurs in a self-propagating mode in a homogeneous thermal film plane field at heating rates above 20K/s and at temperatures above initiation temperature Tin∼180°С. At heating rates lower than 20K/s the mixing of the In and Fe2O3 layers occurs across the whole In/Fe2O3 interface and the synthesis of the ferromagnetic α-Fe phase starts above the initiation temperature Tin=180°С. X-ray diffraction, X-ray photoelectron spectroscopy, Mossbauer spectroscopy, transmission electron microscopy and magnetic measurements were used for phase identification and microstructure observation of the synthesized Fe–In2O3 samples. The reaction products contain (110) textured α-Fe nanocrystals with a diameter around 100nm and surrounded by an In2O3 matrix. These results enable new efficient low-temperature methods for synthesizing ferromagnetic nanocomposite films containing ferromagnetic nanoclusters embedded in transparent conducting oxides.