7681-11-0 Chemical lithiation/delithiation of k+-β-ferrite (k-1+xfe11o17)

The chemical lithiation/delithiation of K+-β-ferrite has been performed using butyllithium, lithium naphthalide (for lithiation), and iodine (for delithiation). In lithiation using butyllithium, the lithium content (y) in K1+xLiyFe11OI7 was dependent on the average grain size of K+-β-ferrite single crystals; small grains (5 μm) largely reacted with lithium to form K0.99Li1.65Fe11O17. Lithiation was performed by the reduction of Fe3+ to Fe2+. Since the same X-ray diffraction (XRD) patterns were obtained before and after lithiation, the reaction seemed to be restricted to only near the grain surfaces. In lithiation using lithium naphthalide, the lithium content (y), which attained to be 36, was independent of the average grain size of K+-β-ferrite single crystals. This lithium content was remarkably large, compared to y = ca. 1.6 in lithiation using butyllithium. A large amount of Fe° (metal) was detected in the samples. According to scanning electron microscope (SEM) and XRD studies, not only pulverization of grains, but also destruction of the β-structure, occurred upon lithiation. On the other hand, delithiation of deeply lithiated samples was achieved by using iodine as an oxidant. https://www.lookchem.com/CASDataBase_7681-11-0.htm

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