In situ and time resolved study of the γ/α-Fe2O3 transition in nanometric particles
作者： T. Belin , N. Millot , N. Bovet , M. Gailhanou
DOI: 10.1016/J.JSSC.2007.06.013
关键词: Diffraction 、 Particle size 、 X-ray crystallography 、 Phase transition 、 Maghemite 、 Surface energy 、 Soft chemistry 、 Crystallography 、 Chemistry 、 Coalescence (physics)
摘要: In situ and real-time study of the {gamma} to {alpha}-Fe{sub 2}O{sub 3} transition is carried out on H10 beamline at LURE (France). {gamma}-Fe{sub particles are synthesized by soft chemistry. These have an average diameter evaluated X-ray diffraction 9{+-}1nm a specific surface area 116m{sup 2}g{sup -1}. The size produced determined in time resolved measurements different temperatures. An amazing evolution with revealed: abrupt doubling particle observed whatever heating temperature. Some assumptions given order explain this phenomenon which implies same energy, granulometric distribution coalescence particles. -- A brutal increase X-rays coherent domain sizes during {gamma}/{alpha} nanometric scale. Maghemite ({phi}=9{+-}1nm) were heated 723 K. First germs (or grains) detected 2 nm.
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