Hematite (α-Fe2O3) with Various Morphologies: Ionic Liquid-Assisted Synthesis, Formation Mechanism, and Properties

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• 作者：Jiabiao Lian ; Xiaochuan Duan ; Jianmin Ma ; Peng Peng ; Tongil Kim ; Wenjun Zheng
• 刊名：ACS Nano
• 出版年：2009
• 出版时间：November 24, 2009
• 年：2009
• 卷：3
• 期：11
• 页码：3749-3761
• 全文大小：740K
• 年卷期：0
• ISSN：1936-086X

文摘

The α-Fe₂O₃ with various morphologies has been successfully synthesized via an ionic liquid-assisted hydrothermal synthetic method. The samples are characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscope (FE-SEM), transmission electron microscopy, and high-resolution transmission electron microscopy. The results indicate that the as-prepared samples are α-Fe₂O₃ nanoparticles, mesoporous hollow microspheres, microcubes, and porous nanorods. The effects of the ionic liquid 1-n-butyl-3-methylimidazolium chloride ([bmim][Cl]) on the formation of the α-Fe₂O₃ with various morphologies have been investigated systematically. The proposed formation mechanisms have also been investigated on the basis of a series of FE-SEM studies of the products obtained at different durations. Because of the unique porous structure, the potential application in water treatment of the α-Fe₂O₃ porous nanorods was investigated. The UV−vis measurements suggest that the as-synthesized pure α-Fe₂O₃ with various morphologies possess different optical properties depending on the shape and size of the samples. The magnetic hysteresis measurements indicate the interesting magnetic property evolution in the as-prepared α-Fe₂O₃ samples, which is attributed to the superstructure or the shape anisotropy of the samples. This method is expected to be a useful technique for controlling the diverse shapes of crystalline inorganic materials for a variety of applications, such as sensors, gas and heavy metal ion adsorbents, catalytic fields, hydrogen and Li ion storage, and controlled drug delivery, etc.