摘要
富磷金属磷化物作为锂离子电池转化型负极材料具有高的理论比容量和合适的电压平台,然而其制备复杂、导电性较差和充放电时产生的剧烈体积变化严重制约了它的发展。为此通过冷冻干燥、模板法以及低温快速磷化制备了CuP_(2)/三维氮掺杂多孔炭复合材料(CuP_(2)@N-PCs),其中利用H2预还原处理前驱体对最终合成富磷相CuP_(2)起到了至关重要的作用。CuP_(2)@NPCs中的三维氮掺杂多孔炭具有出色的稳定性结构、高的电子/离子传导以及丰富的活性位点,起到了改善CuP_(2)作为锂离子电池负极时的电化学性能的作用。所制备的CuP_(2)@N-PCs在1 A/g的电流密度下,经300圈充放电循环后仍能保持827 mAh/g的可逆比容量;在3 A/g的大电流密度下,其可逆比容量也可达到612.2 mAh/g,是一种极具应用前景的锂离子电池负极材料。
Phosphorus-rich metal phosphides as conversion-type anodes of lithium-ion batteries(LIBs) have high theoretical specific capacity and suitable voltage platform. However, the preparation complexity, poor electrical conductivity and volume expansion during charge/discharge seriously restrict the development of P-rich metal phosphides. Therefore, a low-temperature phosphorization method based on H2-reduction treatment is developed to systhesis P-rich phase CuP_(2)@N-PCs from Cu@N-PCs by template method and freezing-dry. The 3D nitrogen-doped porous carbons in the CuP_(2)@N-PCs have excellent stability structure, high electron/ion conduction and abundant active sites, which play a role in improving the electrochemical performance of CuP_(2) as anodes of LIBs. The composite anode can maintain a reversible capacity of 827 mAh/g at 1 A/g after 300 cycles. Even at 3 A/g, its reversible capacity can reach 612.2 mAh/g. The results demonstrate the potential applications of CuP_(2)@N-PCs as electrode materials in next-generation high-specific-energy LIBs.
作者
戴开斌
徐平
邹壬灏
邵俊杰
陆秀清
张宇
黄启忠
苏哲安
Dai Kai-bin;Xu Ping;Zou Ren-hao;Shao Jun-jie;Lu Xiu-qing;Zhang Yu;Huang Qi-zhong;Su Zhe-an(National Key Laboratory of High-strength Structural Materials,Central South University,Hunan Changsha 410083,China)
出处
《炭素技术》
CAS
北大核心
2021年第5期22-27,共6页
Carbon Techniques
关键词
磷化铜
锂离子电池
氮掺杂多孔炭
CuP_(2)
lithium-ion batteries
nitrogen-doped porous carbon
