ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Nanostructured spherical lithium manganese oxide (Li-Mn-O) with about 30nm indiameter was synthesized for the first time by explosive method. The water-solubility explosive wasprepared using a simple facility at room temperature. The growth of lithium manganese oxides viadetonation reaction was investigated with respect to the presence of an energetic precursor, such asthe metallic nitrate and the degree of confinement of the explosive charge. The detonation productswere characterized by scanning electron microscopy. Powder X-ray diffraction and transmissionelectron microscopy were used to characterize the products. Lithium manganese oxides withspherical morphology and more uniform secondary particles, with smaller primary particles ofdiameters from 10 to 50 nm and a variety of morphologies were found. Lithium manganese oxideswith a fine spherical morphology different from that of the normal is formed after detonation wavetreatment due to the very high quenching rate. It might also provide a cheap large-scale synthesismethod. Explosive detonation is strongly nonequilibrium processes, generating a short duration ofhigh pressure and high temperature. Free metal atoms are first released with the decomposition ofexplosives, and then theses metal and oxygen atoms are rearranged, coagulated and finallycrystallized into lithium manganese oxides during the expansion of detonation process. Fordetonation of the water-solubility explosive, the detonation pressure, the detonation temperature andthe adiabatic gamma were close to 3 GPa, 2300 K and 3. The inherent short duration, high heatingrate (1010 – 1011 K/s) and high cooling rate (108 – 109 K/s) prevent the lithium manganese oxidescrystallites from growing into larger sizes and induce considerable lattice distortion
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/52/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.324-325.189.pdf
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