Structural, Optical, and Magnetic Properties of o ‐TbFeO 3 Nanomaterials Synthesized by the co‐Precipitation Method

Following the co‐precipitation method for producing terbium orthoferrite (TbFeO 3 ), the final products were denoted as TbFeO 3 ‐650, −750, and −850. A single‐phase of orthorhombic TbFeO 3 crystals ( o ‐TbFeO 3 ) was obtained with a calcination temperature of up to 850 °C, while in the range of 650–750 °C there was still a small amount of terbium and iron oxide phases. The average size of o ‐TbFeO 3 crystallites for the TbFeO 3 ‐850 sample was about 76 nm and was larger than that of TbFeO 3 ‐650 (~45 nm) and TbFeO 3 ‐750 (~47 nm). The o ‐TbFeO 3 crystal structure in all samples was found to be distorted. In the applied field from −15 to +15 kOe, all of the samples had low values of coercive field (5–11 ⋅ 10 −3 Oe) but high values of net magnetization (2.06–2.40 emu ⋅ g −1 ); the samples appeared to behave as paramagnetic materials. It was shown that the TbFeO 3 ‐850 sample has slightly better magnetic properties than the two others. An average grain size of about 79 nm was found in the TbFeO 3 ‐850 sample, which exhibited a morphology of sphere‐like shapes with highly agglomerated grains. The TbFeO 3 ‐850 sample demonstrated a high absorbance at wavelengths of 400–600 nm, with a direct bandgap of about 2.68 eV.