Nanocrystalline Fe1−xCoxSn2 solid solutions prepared by reduction of salts in tetraethylene glycol
作者:Uche G. Nwokeke、Alan V. Chadwick、Ricardo Alcántara、Maria Alfredsson、José L. Tirado
DOI:10.1016/j.jallcom.2010.11.202
日期:2011.2
improve the electrochemical performance of tin intermetallic phases as electrode active material for lithium-ion batteries, Fe 1− x Co x Sn 2 solid solutions with x = 0.0, 0.25, 0.3, 0.5, 0.6 and 0.8 were prepared by chemical reduction in tetraethylene glycol. Precise control of the synthesis conditions allowed single-phase nanocrystalline materials to be prepared, with particle diameters of about 20 nm
摘要 为了提高作为锂离子电池电极活性材料的锡金属间相的电化学性能,制备了 x = 0.0、0.25、0.3、0.5、0.6 和 0.8 的 Fe 1− x Co x Sn 2 固溶体。四乙二醇中的化学还原。合成条件的精确控制允许制备单相纳米晶材料,其粒径约为 20 nm 和立方体、纳米棒和 U 形形态。钴取代铁导致晶胞体积收缩。57 Fe Mossbauer 光谱的超精细参数对 Co/Fe 取代敏感,并显示出超顺磁行为。在锂电池中,纳米晶 Fe 1- x Co x Sn 2 活性材料提供高于 500 mAh g -1 的可逆容量,这取决于成分和循环条件。中间组合物表现出比最终组合物CoSn 2 和FeSn 2 更好的电化学性能。