Features of the Thermal Behavior and Phase Formation of BiFeO₃ Using Precursors Activated by Solar Melting

The effect of pretreatment of Bi2O3 and Fe2O3 oxides on the synthesis and structural characteristics of bismuth ferrite BiFeO3 was studied. It was found that BiFeO3 formation begins at 790÷850 °C, and decomposition occurs above ~920 °C. Preliminary melting of the oxides in a solar furnace shifts the thermal effects to higher temperatures and increases the thermodynamic stability of the phase. X-ray phase analysis revealed the formation of a perovskite-like structure with orthorhombic distortion, high crystallinity, and a crystallite size of 40±10 nm. Phase analysis confirmed an increase in the content of the main phase to 97 % and a decrease in the impurity phase Bi2Fe4O9. The obtained results confirm the efficiency of preliminary solar melting of oxides for the synthesis of high-quality ceramic materials based on BiFeO3.