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以聚丙烯腈(PAN),N,N-二甲基甲酰胺(DMF)和钴盐为前驱体,通过对有机凝胶进行高温碳化得到钴负载碳气凝胶.利用X射线衍射谱(XRD),扫描电镜(SEM),透射电镜(TEM),热重分析(TGA)和充放电测试对钴负载碳气凝胶进行结构、形貌和电化学性能的表征分析.结果表明,碳化温度影响产物的形貌及性能,其中700℃碳化的钴负载碳气凝胶钴颗粒分布最均匀,同时具有最好的电化学性能.在50mA·g~(-1)电流密度下,首次放电比容量高达983.1mAh·g~(-1),经100周循环后,放电比容量仍保持在280.3mAh·g~(-1);在500mA·g~(-1)大电流密度下,该材料放电比容量为105.4mAh·g~(-1),具有很好的倍率性能.
Cobalt-supported carbon aerogels were obtained by carbonization of organogel with polyacrylonitrile (PAN), N, N-dimethylformamide (DMF) and cobalt salts as precursors.Using XRD ), SEM, TEM, TGA and charge-discharge tests were used to characterize the structure, morphology and electrochemical performance of cobalt loaded aerogels. The results show that the effect of carbonation temperature The morphology and properties of the products were characterized by the most uniform distribution of the cobalt-loaded cobalt-airgel cobalt particles at 700 ℃ and the best electrochemical performance.At the current density of 50mA · g ~ (-1), the initial discharge specific capacity As high as 983.1mAh · g -1, the specific discharge capacity remained at 280.3mAh · g -1 after 100 cycles. Under the high current density of 500mA · g -1, the material discharged Specific capacity of 105.4mAh · g ~ (-1), with good rate performance.