论文标题
1T期Al-Mos $ _ {2} $@RGO纳米复合材料作为钠离子电池的高性能阳极的扩散机制和电化学研究
Diffusion mechanism and electrochemical investigation of 1T phase Al-MoS$_{2}$@rGO nano-composite as a high-performance anode for sodium-ion batteries
论文作者
论文摘要
我们报告了5％Al掺杂MOS $ _2 $@RGO复合材料的电化学调查，作为钠（NA）-OIN电池的高性能阳极。 X射线衍射（XRD），拉曼光谱和高分辨率透射电子显微镜表征表明，Al掺杂增加了MOS $ _2 $纳米片的（002）平面的层间间距，并形成稳定的1T相。电静态电荷分离测量表明，分别为0.05、0.1、0.3、0.5、0.5、0.5、0.5、0.5和1〜Ag $^{ - 1} $的特定容量稳定在450、400、400、350、300和200 mahg $^{ - 1} $。此外，我们观察到在0.1和0.3 ag $^{ - 1} $的容量保留量为86％和66％，超过200个周期，其一致的库仑效率近100％。循环伏安法，镀锌间歇性滴定技术和电化学阻抗光谱用于查找动力学行为和扩散系数获得的价值，范围为10 $^{ - 10} $ to 10 $^{ - 12 $^{ - 12} $ cm $ cm $ cm $^2 $^2 $^2 $ s $ s $ s $ s $ s $ s $^$^ - 1} $ 1}。有趣的是，原位EIS还解释了电荷转移电阻变化的不同电荷分离状态下电极的电化学动力学。此外，使用Ex-Situ XRD和光发射光谱的循环研究表明，1T/2H相和田间发射扫描电子显微镜的共存证实了500个周期后的稳定形态。此外，根据1T al-mos $ _2 $@rgo接口和al--mos $ _2 $ - MOS $ _2 $使用密度函数理论计算，计算Na-ion传输属性。
We report the electrochemical investigation of 5% Al doped MoS$_2$@rGO composite as a high-performance anode for sodium (Na)-ion batteries. The x-ray diffraction (XRD), Raman spectroscopy and high-resolution transmission electron microscopy characterizations reveal that the Al doping increase the interlayer spacing of (002) plane of MoS$_2$ nanosheets and form a stable 1T phase. The galvanostatic charge-discharge measurements show the specific capacity stable around 450, 400, 350, 300 and 200 mAhg$^{-1}$ at current densities of 0.05, 0.1, 0.3, 0.5 and 1~Ag$^{-1}$, respectively. Also, we observe the capacity retentions of 86% and 66% at 0.1 and 0.3 Ag$^{-1}$, respectively, over 200 cycles with a consistent Coulombic efficiency of nearly 100%. The cyclic voltammetry, galvanostatic intermittent titration technique, and electrochemical impedance spectroscopy are used to find the kinetic behavior and the obtained value of diffusion coefficient falls in the range of 10$^{-10}$ to 10$^{-12}$ cm$^2$s$^{-1}$. Intriguingly, the in-situ EIS also explains the electrochemical kinetics of the electrode at different charge-discharge states with the variation of charge transfer resistance. Moreover, the post cycling investigation using ex-situ XRD and photoemission spectroscopy indicate the coexistence of 1T/2H phase and field-emission scanning electron microscopy confirm the stable morphology after 500 cycles. Also, the Na-ion transport properties are calculated for 1T Al--MoS$_2$@rGO interface and Al--MoS$_2$--MoS$_2$ interlayer host structure by theoretical calculations using density functional theory.
