title: A new method for the identification and quantification of magnetite-maghemite mixture using conventional X-ray diffraction technique.
abstract: The electrical explosion of Fe wire in air produced nanoparticles containing the binary mixture of magnetite (Fe(3)O(4)) and maghemite (γ-Fe(2)O(3)). The phase identification of magnetite and maghemite by the conventional X-ray diffraction method is not a simple matter because both have the same cubic structure and their lattice parameters are almost identical. Here, we propose a convenient method to assess the presence of magnetite-maghemite mixture and to further quantify its phase composition using the conventional peak deconvolution technique. A careful step scan around the high-angle peaks as (511) and (440) revealed the clear doublets indicative of the mixture phases. The quantitative analysis of the mixture phase was carried out by constructing a calibration curve using the pure magnetite and maghemite powders commercially available. The correlation coefficients, R(2), for magnetite-maghemite mixture was 0.9941. According to the method, the iron oxide nanoparticles prepared by the wire explosion in this study was calculated to contain 55.8 wt.% maghemite and 44.2 wt.% magnetite. We believe that the proposed method would be a convenient tool for the study of the magnetite-maghemite mixture which otherwise requires highly sophisticated equipments and techniques.
authors.affiliation: Korea Institute of Geoscience & Mineral Resources (KIGAM), Gwahang-no 124, Yuseong-gu, Daejeon, 305- 350, Republic of Korea.
authors.forename: Wonbaek
authors.initials: W
authors.lastname: Kim
authors.forename: Chang-Yul
authors.initials: CY
authors.lastname: Suh
authors.forename: Sung-Wook
authors.initials: SW
authors.lastname: Cho
authors.forename: Ki-Min
authors.initials: KM
authors.lastname: Roh
authors.forename: Hanjung
authors.initials: H
authors.lastname: Kwon
authors.forename: Kyungsun
authors.initials: K
authors.lastname: Song
authors.forename: In-Jin
authors.initials: IJ
authors.lastname: Shon
mesh_terms: D004560:Electricity; D005107:Explosions; D005290:Ferric Compounds / Q000032:analysis* / Q000737:chemistry; D052203:Ferrosoferric Oxide / Q000032:analysis* / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry; D010316:Particle Size; D011208:Powders; D014961:X-Ray Diffraction
chemical_list: D005290:Ferric Compounds; D011208:Powders; C000499:ferric oxide; D007501:Iron; D052203:Ferrosoferric Oxide