高性能氮掺杂中空碳纳米盒的制备及其在钠离子负极中的应用

Preparation of High Performance Nitrogen Doped Hollow Carbon Box and Their Application in Sodium Anode

碳基材料由于价格低廉、导电性良好及无毒安全等优势,成为钠离子电池中具有吸引力的负极材料,研究表明通过构筑利于电荷传输的动力学结构和引入杂原子进行掺杂,可改善其储钠离子的性能。采用模板法制备了氮掺杂中空碳纳米盒(NHCC),独特的中空纳米盒结构一方面能提供与电解质更大的接触面积,另一方面有利于离子的高效稳定传输。此外,NHCC材料引入氮原子能有效增加碳基材料的缺陷结构,为钠离子的储存提供更多的活性位点。研究结果表明,NHCC材料在电化学性能方面表现出优良的倍率性能(在电流密度2000 mA·g^(-1)下容量为220.7 mAh·g^(-1))和良好的循环性能(在电流密度200 mA·g^(-1)下循环400次后的可逆容量为255.7 mAh·g^(-1)),同时通过动力学分析可得NHCC材料的表面赝电容行为有利于钠离子的存储。因此,氮掺杂中空碳纳米盒可为钠离子电池碳基负极材料提供新思路。

Due to the advantages of low cost,good conductivity and high safety,carbon-based materials have become attractive anode materials in sodium ion batteries.At present,it has been reported that the sodium storage performance can be improved by constructing a dynamic structure conducive to charge transfer and introducing impurity atoms to doping.In this study,nitrogen doped hollow carbon box(NHCC)was prepared by the template method,which is characterized by a complete hollow nanobox structure.The unique hollow nanobox structure can provide a larger contact area with the electrolyte.Besides,it is conducive to the efficient and stable transmission of ions.In addition,the introduction of nitrogen atoms into NHCC materials can effectively increase the defect structure of carbon materials and provide more active sites for the storage of sodium ions.The experimental results showed that the NHCC materials presented excellent rate performance with 220.7 mAh·g^(-1)at 2000 mA·g^(-1),and sound repeatable sodium storage capability characterized by a reversible capacity of 255.7 mAh·g^(-1)at 200 mA·g^(-1)after 400 cycles.Therefore,nitrogen doped hollow carbon box provide a new solution for carbon based anode materials of sodium ion batteries.