Abstract In this study, a bismuth ferrite (BiFeO3) nanopowder was synthesized by combining Bi(NO3)3·5H2O, Fe(NO3)3·9H2O, and NaOH raw materials in the presence of polyethylene glycol (PEG) with varying polymerization degrees (i.e. PEG200, PEG400, PEG600, and PEG10000). The synthesis process was carried out by room-temperature solid-state reaction followed by subsequent secondary solid-state reaction at 550 °C. The results suggested a significant influence of PEG polymerization degree on the morphology and size of the as-synthesized products. The grain size decreased after the introduction of PEG but increased with the polymerization degree. The vibrating-sample magnetometry data revealed PEG400 and PEG600 with obvious room-temperature ferromagnetism properties. In UV–Vis spectroscopy, the absorption edge exhibited a blue shift as the polymerization degree of PEG rose. In sum, BiFeO3 nanopowder possessed room-temperature ferromagnetism, thereby suitable photocatalyst for wastewater treatment and environmental purification with convenient recycling and substantial economic value.

中文翻译：

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聚乙二醇辅助两步固相反应制备新型铋铁氧体纳米粉体：合成及磁光性能

摘要 本研究以Bi(NO3)3·5H2O、Fe(NO3)3·9H2O、NaOH为原料，在不同聚合度的聚乙二醇(PEG)存在下，合成了一种铁氧体铋(BiFeO3)纳米粉体。即 PEG200、PEG400、PEG600 和 PEG10000)。合成过程通过室温固相反应进行，随后在 550 °C 下进行二次固相反应。结果表明 PEG 聚合度对合成产物的形态和大小有显着影响。加入PEG后晶粒尺寸减小，但随着聚合度的增加而增大。振动样品磁力计数据显示PEG400和PEG600具有明显的室温铁磁性。在紫外-可见光谱中，随着PEG聚合度的升高，吸收边呈现蓝移。综上所述，BiFeO3纳米粉体具有室温铁磁性，是一种适用于废水处理和环境净化的光催化剂，回收利用方便，具有巨大的经济价值。