Thermal decomposition of barium ferrate(VI): Mechanism and formation of FeIV intermediate and nanocrystalline Fe2O3 and ferrite

JOURNAL OF ALLOYS AND COMPOUNDS

卷:668

Article

Machala, Libor¹  Sharma, Virender K.²  Kuzmann, Ernoe³  Homonnay, Zoltan³  Filip, Jan¹  Kralchevska, Radina P.¹ 

[1] Palacky Univ, Fac Sci, Dept Expt Phys, Reg Ctr Adv Technol & Mat, CR-77147 Olomouc, Czech Republic

[2] Texas A&M Univ, Sch Publ Hlth, Dept Environm & Occupat Hlth, 1266 TAMU, College Stn, TX 77843 USA

[3] Eotvos Lorand Univ, Inst Chem, Budapest, Hungary

关键词: Solid state reactions;    Hyperfine interactions;    Mossbauer spectroscopy;    Thermal analysis;    X-ray diffraction;   

DOI  :  10.1016/j.jallcom.2016.01.185

来源: Elsevier

【 摘 要 】

Simple high-valent iron-oxo species, ferrate(VI) ((FeO42-)-O-VI, Fe(VI)) has applications in energy storage, organic synthesis, and water purification. Of the various salts of Fe(VI), barium ferrate(VI) (BaFeO4) has also a great potential as a battery material. This paper presents the thermal decomposition of BaFeO4 in static air and nitrogen atmosphere, monitored by combination of thermal analysis, Mossbauer spectroscopy, X-ray powder diffraction, and electron-microscopic techniques. The formation of Fe-IV species in the form of BaFeO3 was found to be the primary decomposition product of BaFeO4 at temperature around 190 degrees C under both studied atmospheres. BaFeO3 was unstable in air reacting with CO2 to form barium carbonate and speromagnetic amorphous iron(III) oxide nanoparticles (<5 nm). Above 600 degrees C, a solid state reaction between BaCO3 and Fe2O3 occurred, leading to the formation of barium ferrite nanoparticles, BaFe2O4 (20-100 nm). (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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