氟掺杂对Na₂Ti₃O₇作为钠离子电池负极材料电化学性能的影响

Chen Zehua, Lu Liang, Gao Yu, Zhang Qixiang, Zhang Chuanxiang, Sun Chunwen, Chen Xingying

College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 54000, China.

School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.

Materials (Basel). 2018 Nov 7;11(11):2206. doi: 10.3390/ma11112206.

The effects of fluorine (F) doping on the phase, crystal structure, and electrochemical performance of Na₂Ti₃O₇ are studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical measurements. F-doping does not change the crystal structure of NTO, although it has an effect on the morphology of the resultant product. As an anode material for sodium-ion batteries, the specific capacity of Na₂Ti₃O₇ exhibits a 30% increase with F-doping owing to the improved sodium ion diffusion coefficient. F-doped Na₂Ti₃O₇ also displays an enhanced rate capability and favourable cycling performance for more than 800 cycles.

通过X射线衍射（XRD）、扫描电子显微镜（SEM）和电化学测量研究了氟（F）掺杂对Na₂Ti₃O₇的相、晶体结构和电化学性能的影响。F掺杂虽对所得产物的形貌有影响，但不改变NTO的晶体结构。作为钠离子电池的负极材料，由于钠离子扩散系数的提高，F掺杂使Na₂Ti₃O₇的比容量提高了30%。F掺杂的Na₂Ti₃O₇还表现出增强的倍率性能和超过800次循环的良好循环性能。