Observation of low- and high-temperature CuFe2O4 phase at 1100 degrees C: The influence of Fe3+ ions on CuFe2O4 structural transformation

Samples containing CuFe2O4 and CuO nanoparticles were synthesized by coprecipitation method and subjected to thermal treatment at 300 degrees C, 500 degrees C, 700 degrees C, 900 degrees C and 1100 degrees C. Depending on the synthesis conditions, high temperature treatment of the prepared samples brought to the formation of CuFe2O4 with a tetragonal or cubic structure, which was confirmed by X-ray diffraction analysis. The influence of formation mechanism onto the crystallite sizes of nanoparticles and structural transformation of CuFe2O4 is discussed. For the first time it was shown that variations of the initial amount of Fe3+ and Cu2+ ions precursors resulted in the formation of low and high-temperature CuFe2O4 phase at the same annealing temperature, 1100 degrees C.