Li Intercalation in MoS2: In Situ Observation of Its Dynamics and Tuning Optical and Electrical Properties
Li Intercalation in MoS2: In Situ Observation of Its Dynamics and Tuning Optical and Electrical Properties
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DOI：
10.1021/acs.nanolett.5b02619
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发表时间：
2015-10-01
期刊：
影响因子：
10.8
通讯作者：
Cui, Yi
中科院分区：
文献类型：
--
作者：
Xiong, Feng;Wang, Haotian;Cui, Yi
像MoS2这样的二维层状材料已经显示出在纳米电子学和能量存储方面的前景，无论是作为单层材料还是作为具有可调特性的块状范德华晶体。在这里，我们提出了一个平台，通过电化学方式将外来物质（Li+离子）插入其层间距来调整纳米级MoS2的物理和化学性质。我们发现，由于能带结构的变化减少了嵌入时的吸收和大量自由载流子的注入，在嵌入锂后，超薄（类似于 2-50 nm）MoS2 纳米片的透光率（在 4 nm 厚的锂化 MoS2 中高达 90%）和电导率（超过 200 倍）显着增强。我们还首次对 MoS2 纳米片中的 Li 嵌入进行了原位光学观察，揭示了嵌入过程的动力学以及相关的空间不均匀性和循环引起的结构缺陷。
Two-dimensional layered materials like MoS2 have shown promise for nanoelectronics and energy storage, both as monolayers and as bulk van der Waals crystals with tunable properties. Here we present a platform to tune the physical and chemical properties of nanoscale MoS2 by electrochemically inserting a foreign species (Li+ ions) into their interlayer spacing. We discover substantial enhancement of light transmission (up to 90% in 4 nm thick lithiated MoS2) and electrical conductivity (more than 200x) in ultrathin (similar to 2-50 nm) MoS2 nanosheets after Li intercalation due to changes in band structure that reduce absorption upon intercalation and the injection of large amounts of free carriers. We also capture the first in situ optical observations of Li intercalation in MoS2 nanosheets, shedding light on the dynamics of the intercalation process and the associated spatial inhomogeneity and cycling-induced structural defects.