title: Hematite (alpha-Fe2O3) with various morphologies: ionic liquid-assisted synthesis, formation mechanism, and properties.
abstract: The alpha-Fe(2)O(3) 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 alpha-Fe(2)O(3) 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 alpha-Fe(2)O(3) 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 alpha-Fe(2)O(3) porous nanorods was investigated. The UV-vis measurements suggest that the as-synthesized pure alpha-Fe(2)O(3) 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 alpha-Fe(2)O(3) 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.
authors.affiliation: Department of Materials Chemistry, College of Chemistry, Nankai University, Tianjin, P. R. China.
authors.forename: Jiabiao
authors.initials: J
authors.lastname: Lian
authors.forename: Xiaochuan
authors.initials: X
authors.lastname: Duan
authors.forename: Jianmin
authors.initials: J
authors.lastname: Ma
authors.forename: Peng
authors.initials: P
authors.lastname: Peng
authors.forename: Tongil
authors.initials: T
authors.lastname: Kim
authors.forename: Wenjun
authors.initials: W
authors.lastname: Zheng