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PrMnO precursor was synthesized by solid-state reaction at low temperatures using Pr(NO)⋅6HO, MnSO⋅HO, and NaCO as raw materials. PrMnO was obtained by calcining a precursor, 1.1/2Pr(CO)-MnCO⋅5.3HO, over 1,000 C in air. The precursor and its calcined products were characterized by thermogravimetry and differential scanning calorimetry, X-ray powder diffraction, scanning electron microscopy, and vibrating sample magnetometer. A high-crystallized PrMnO with an orthorhombic structure was obtained when the precursor was calcined over 1,000 C in air for 2 h. Magnetic characterization indicated that orthorhombic PrMnO behaved with weak magnetic properties. The thermal transformation of the precursor from ambient temperature to 1,050 C in air presented four steps: the dehydration of 5.3 crystal waters; the reaction of MnCO with 0.75O into 1/2MnO and the two CO molecules; the reaction of 1.1/2Pr(CO) with 0.825O into 1.1/2PrOCO and of 2.75CO molecules; and the reaction of 1.1/2PrOCO with 1/2MnO into PrMnO and 0.55CO [ABSTRACT FROM AUTHOR]

MgZnFe(CO)⋅HO was synthesized by solid-state reaction at low heating temperatures using MgSO⋅7HO, ZnSO⋅7HO, FeSO⋅7HO, and NaCO as raw materials. The spinel MgZnFeO was obtained via calcining MgZnFe(CO)⋅HO above 400 °C for 1 h in air. The MgZnFe(CO)⋅HO and its calcined products were characterized by thermogravimetry and differential scanning calorimetry (TG/DSC), Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). The results showed that MgZnFeO obtained at 400 °C had a specific saturation magnetization of 27.3 emu g. The thermal process of MgZnFe(CO)⋅HO experienced three steps, which are: first, the dehydration of water of crystallization and decomposition of MgZnCO into MgO and ZnO, then the reaction of Fe(CO) with MgO and ZnO into amorphous MgZnFeO, and at last the crystallization of MgZnFeO. Based on the KAS equation and the OFW equation, the values of the activation energies associated with the thermal process of MgZnFe(CO)⋅HO were determined to be 69±11 and 71±9 kJ mol for the first and second thermal process steps, respectively. [ABSTRACT FROM AUTHOR]