题目： Improving ionic/electronic conductivity of MoS₂Li-ion anode via manganese doping and structural optimization

作者： Jiacheng Wang¹，Liyang Zhang¹，Kuan Sun¹，Junjie He²*，Yujie Zheng¹，Chaohe Xu¹, Yuxin Zhang¹，Yu Chen³*，Meng Li¹*

单位： 1. MOE Key Laboratory of Low-grade Energy Utilization Technologies and Systems, CQU-NUS Renewable Energy Materials & Devices Joint Laboratory, School of Energy & Power Engineering, Chongqing University, Chongqing 400044, China

2. School of Science, Chongqing University of Posts and Telecommunications, Chongqing 400065, China

3. School of Optoelectronic Science and Engineering & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China

摘要： Developing anode materials for lithium-ion batteries with excellent electrochemical performance is crucial to satisfy the requirement for energy storage. Molybdenum disulfide is recognized as a prospective anode material due to its high theoretical capacity and two-dimensional layered structure. However, its further application is mainly hindered by its poor electronic conductivity. Herein, we report Mn-doped MoS₂ nanosheets anchored on hierarchical carbon skeleton (MMSC) acting as an anode material. The as-synthesized electrode exhibits a high initial discharge capacity of 1280mAhg⁻¹ at a current density of 0.1Ag⁻¹, high rate capacity (920mAhg⁻¹ at 2Ag⁻¹), and long-time cycling stability (71% capacity retention after 1000 cycle). Compared to that of pristine MoS₂ electrode, the improved performance of MMSC anode can be attributed to the synergetic effects of optimized composite structure and Mn doping. The hierarchical carbon skeleton provides a larger surface area, allowing effective electrolyte penetration and preventing aggregation of MoS₂ nanosheets in charge/discharge cycles. To further understand the mechanism of the improved rate capability, calculation of corresponding atomic models according to experimental results and first-principles calculation are conducted. The calculated results prove that the Mn-doped MoS₂(MMS) has a lower diffusion barrier of Li⁺ than that in pristine MoS₂. Moreover, the as-synthesized MMSC electrode also demonstrates better electronic conductivity because of the electronic injection by Mn atoms.

影响因子： 6.735

分区情况： 一区

链接： https://www.sciencedirect.com/science/article/pii/S1385894719309891?via%3Dihub