Li-Ion Storage Performance of Carbon-Coated Mn–Al–O Composite Oxides
Autor: | Yong-Xin Qi, Gui-Xia Lu, Hui-Ling Zhu, Ning Lun, Cheng Wei, Yu-Jun Bai, Yunkai Sun, Ning Zhao, Tao Li |
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Rok vydání: | 2014 |
Předmět: | |
Zdroj: | The Journal of Physical Chemistry C. 118:23559-23566 |
ISSN: | 1932-7455 1932-7447 |
Popis: | The composites of manganese oxide and alumina (Mn–Al–O) with varied Mn/Al molar ratios were fabricated by a simple coprecipitation method and subsequently sintered at different temperatures. Carbon-coated oxides were prepared at 550 °C using pyrrole as the carbon source. Compared with the carbon-coated MnO prepared under the same conditions, the carbon-coated Mn–Al–O exhibits greatly enhanced electrochemical performance which is associated with both the Mn/Al molar ratio and sintering temperature. The carbon-coated composites with a ratio of 2:1 sintered at 600 °C could deliver a stable reversible capacity of 450 mAh g–1 after 100 cycles at a current density of 100 mA g–1 and the capacities of 373, 309, 245, and 175 mAh g–1 at the densities of 200, 400, 800, and 1600 mA g–1, respectively. The enhanced cycling and rate performance is attributed to the improved Li-ion conductivity owing to the formation of LiAlO2 and the smaller particle size of MnO due to the dispersion effect of Al2O3. |
Databáze: | OpenAIRE |
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