Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China.
Nanoscale. 2020 Jan 2;12(2):1144-1154. doi: 10.1039/c9nr07646h.
MoS2 is a promising anode candidate for high-performance lithium-ion batteries (LIBs) due to its unique layered structure and high specific capacity. However, the poor conductivity and unsatisfactory structural stability limit its practical application. Recently, a new class of 2D materials, V4C3-Mxene, has been found to combine metallic conductivity, high structural stability and rich surface chemistries. Herein, a facile method has been developed to fabricate V4C3-MXene/MoS2/C nanohybrids. Ultrasmall and few-layered MoS2 nanosheets are uniformly anchored on the surface of V4C3-MXene with a thin carbon-coating layer. The ultrasmall and few-layered MoS2 nanosheets can enlarge the specific areas, reduce the diffusion distance of lithium ions, and accelerate the transfer of charge carriers. As a supporting substrate, V4C3-MXene endows the nanohybrid with high electrical conductivity, strong structural stability, and fast reaction kinetics. Moreover, the carbon-coating layer can further enhance the electrical conductivity and structural stability of the hybrid material. Benefiting from these advantages, the V4C3-MXene/MoS2/C electrode shows an excellent cycling stability with a high reversible capability of 622.6 mA h g-1 at 1 A g-1 after 450 cycles, and a superior rate capability of 500.0 mA h g-1 at 10 A g-1. Thus, the V4C3-MXene/MoS2/C nanohybrid could become a promising anode material for high rate LIBs.
二硫化钼(MoS2)因其独特的层状结构和高比容量,是一种很有前途的高性能锂离子电池(LIBs)的阳极候选材料。然而,其较差的导电性和不理想的结构稳定性限制了其实际应用。最近,一类新的二维材料——V4C3-Mxene,被发现兼具金属导电性、高结构稳定性和丰富的表面化学性质。在此,我们提出了一种简便的方法来制备 V4C3-MXene/MoS2/C 纳米杂化物。超小和少层的 MoS2 纳米片均匀地锚定在 V4C3-MXene 的表面上,并具有薄的碳涂层。超小和少层的 MoS2 纳米片可以增大比表面积、减小锂离子的扩散距离并加速电荷载流子的转移。作为支撑基底,V4C3-MXene 赋予纳米杂化物高导电性、强结构稳定性和快速反应动力学。此外,碳涂层还可以进一步提高混合材料的导电性和结构稳定性。得益于这些优势,V4C3-MXene/MoS2/C 电极在 450 次循环后以 1 A g-1 的电流密度具有 622.6 mA h g-1 的高可逆容量和以 10 A g-1 的电流密度具有 500.0 mA h g-1 的优异倍率性能。因此,V4C3-MXene/MoS2/C 纳米杂化物有望成为高倍率 LIBs 的一种有前途的阳极材料。