Reduction Processes in the Course of Mechanochemical Synthesis of Li1+xV3O8

✍ Scribed by N.V. Kosova; S.V. Vosel; V.F. Anufrienko; N.T. Vasenin; E.T. Devyatkina

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 299 KB
• Volume: 160
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2001.9272

✦ Synopsis

Mechanical activation (MA) of the LiOH ؉ V 2 O 5 and Li 2 CO 3 ؉ V 2 O 5 mixtures followed by brief heating at 673 K was used to prepare dispersed Li 1؉x V 3 O 8 . It was shown that structural transformations during MA are accompanied by reduction processes. EPR spectra of Li 1؉x V 3 O 8 are attributed to vanadyl VO 2؉ ions with weak exchange interaction. The interaction of localized electrons (V 4؉ ions) with electron gas (delocalized electrons), which is exhibited through the dependence of EPR line width of vanadium ions versus measurement temperature (C+S+C relaxation), is revealed. It is shown that C+S+C relaxation is di4erent for intermediate and 5nal products. The properties of mechanochemically prepared Li 1؉x V 3 O 8 are compared with those of HT-Li 1؉x V 3 O 8 , obtained by conventional solid state reaction. Mechanochemically prepared Li 1؉x V 3 O 8 is characterized by a similar amount of vanadium ions, producing electron gas, but a higher speci5c surface area.