• 文献标题:   Design of ultra-thick graphene-molybdenum disulfide electrodes to reduce volume expansion and capacity fading by first principles
  • 文献类型:   Article
  • 作  者:   JIA ZG, ZHANG XX, QIAN MF, MA SY, JIN YM, XIONG YP
  • 作者关键词:   lithiumion batteries libs, hydrothermal synthesi, molybdenum disulfide mos2, reduced graphene oxide rgo, firstprinciples calculation
  • 出版物名称:   JOURNAL OF ALLOYS COMPOUNDS
  • ISSN:   0925-8388 EI 1873-4669
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1016/j.jallcom.2022.168623 EA JAN 2023
  • 出版年:   2023

▎ 摘  要

The shuttling of polysulfide intermediates and volume distortion during cycling make it challenging for the applications of MoS2 at high current densities without capacity fading. In order to improve the cycle life and rate capability of lithium-ion batteries, introducing a porous matrix is a viable strategy. Here, MoS2 with 3D porous graphene prepared by low-temperature hydrothermal (160 degrees C) and low-energy ultrasound-assisted (40 W for 120 s) methods shows no impurities, large layer thickness (0.94 nm, 54 % increase) and no bare MoS2, resulting in smaller volume expansion (34 % in Li4MoS2), higher lithium stability (0.66 eV of ad-sorption energy) and more convenient ion transport channels. The first-principles calculations show that more lithium can be inserted without destroying the layered structure by forming a lithium metal layer between the MoS2 layers. The encapsulation of graphene not only hinders the shuttle effect of sulfur, but also improves the adsorption energy of lithium atoms in the electrode. In addition, electrochemical analysis shows that the clear drop in charge transfer resistance (Rct) in the first 300 cycles also indicates the im-provement of the reaction pathway by graphene. As a result, the as-prepared rGO/MoS2 still maintains a specific capacity of 1008 mAhmiddotg-1 with a very low capacity decay rate (0.03 % per cycle) at a current density of 1 Amiddotg-1 after 500 cycles as an electrode material for lithium-ion batteries.(c) 2023 Elsevier B.V. All rights reserved.