title: Two-step self-assembly of iron oxide into three-dimensional hollow magnetic porous microspheres and their toxic ion adsorption mechanism.
abstract: Hollow magnetic porous Fe(3)O(4)/α-FeOOH microspheres, with abundant surface hydroxyl groups and carbonate-like species, were prepared using a simple template free solution method. The obtained magnetic microspheres were characterized by field emission scanning electron microscopy, transmission electron microscopy, nitrogen adsorption-desorption isotherms, vibrating sample magnetometry and X-ray diffraction. A two-step self-assembly mechanism for the microspheres was proposed based on the morphology of the products produced with different reaction times and the X-ray diffraction of the raw product grown at the initial stage. The toxic ion adsorption properties of the microspheres were investigated for As(V), Cr(VI), Cd(II) and Hg(II) ion removal. The adsorption mechanism was studied by an X-ray photoelectron spectrometer and Fourier transform infrared absorption spectroscopy . The results suggest that both the surface hydroxyl groups and the carbonate-like species participated in the ion-exchange process.
authors.affiliation: Research Center for Biomimetic Functional Materials and Sensing Devices, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031, PR China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Jia
authors.forename: Xin-Yao
authors.initials: XY
authors.lastname: Yu
authors.forename: Tao
authors.initials: T
authors.lastname: Luo
authors.forename: Mei-Yun
authors.initials: MY
authors.lastname: Zhang
authors.forename: Jin-Huai
authors.initials: JH
authors.lastname: Liu
authors.forename: Xing-Jiu
authors.initials: XJ
authors.lastname: Huang
mesh_terms: D000327:Adsorption; D005290:Ferric Compounds / Q000737:chemistry*; D052203:Ferrosoferric Oxide / Q000737:chemistry; D008280:Magnetics; D008670:Metals / Q000302:isolation & purification; D016062:Porosity; D014961:X-Ray Diffraction
chemical_list: D005290:Ferric Compounds; D008670:Metals; C000499:ferric oxide; D052203:Ferrosoferric Oxide