Effect of the air oxidation stabilization of pitch on the microstructure and sodium of hard carbons
Effect of the air oxidation stabilization of pitch on the microstructure and sodium of hard carbons
复制标题
沥青空气氧化稳定对硬碳微观结构和钠储存的影响
DOI：
10.1016/s1872-5805(21)60075-6
复制
发表时间：
2021-12-24
影响因子：
5.7
通讯作者：
Zhou, Ying
中科院分区：
文献类型：
--
作者：
Guo, Hong-yi;Li, Yao-yu;Zhou, Ying
以石油沥青为原料，采用空气氧化稳定后炭化的方法制备了钠离子电池硬炭负极材料。研究了氧化稳定化温度对氧化样品的成分和显微结构的影响，以及氧化稳定化温度对氧化样品的形貌、显微结构和贮钠性能的影响。结果表明，空气氧化引入了大量含氧官能团，引发了脱氢缩合和氧化交联反应，使石油沥青由热塑性转变为热固性。空气氧化稳定化处理有效地阻碍了沥青在高温碳化过程中石墨化的固有趋势，导致具有随机取向的碳层的碳具有更多的缺陷。电化学测试表明，o-PDC-350-1400（350 ℃氧化稳定，1400 ℃碳化）在100 mA g（-1）下具有276.8 mAh g（-1）的高充电比容量和73.38%的高初始库仑效率。与在1400 ℃下直接焙烧的样品PDC-1400相比，充电比容量增加约1.8倍，初始库仑效率增加22%。o-PDC-350-1400在200次循环后的充电比容量达到170.2mAh g（-1），表明良好的循环稳定性。
Hard carbon anode materials for sodium ion batteries were prepared from petroleum pitch by air oxidation stabilization followed by carbonization. The effects of the oxidation stabilization temperature on the compositions and microstructures of the oxidized samples, as well as on the morphology, microstructure and sodium storage property of the carbonized samples were investigated. Results show that air oxidation introduces a large number of oxygen-containing functional groups, induces dehydrogenation condensation and oxidative crosslinking reactions, and transforms the petroleum asphalt from thermoplastic to thermosetting. The air oxidation stabilization treatment effectively hinders the inherent tendency of asphalt to graphitize during high temperature carbonization, resulting in carbons with randomly oriented carbon layers with more defects. Electrochemical tests show that o-PDC-350-1400 (oxidation stabilization at 350 degrees C, carbonization at 1400 degrees C) has a high charging specific capacity of 276.8 mAh g(-1) at 100 mA g(-1) and a high initial coulombic efficiency of 73.38%. Compared with sample PDC-1400 that was directly carbonized at 1400 degrees C, the charging specific capacity was increased by about 1.8 times and the initial coulombic efficiency was increased by 22%. The charging specific capacity of o-PDC-350-1400 after 200 cycles reached 170.2 mAh g(-1), indicating good cycling stability.