Raman Spectra of ZrS2 and ZrSe2 from Bulk to Atomically Thin Layers
Raman Spectra of ZrS2 and ZrSe2 from Bulk to Atomically Thin Layers
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DOI：
10.3390/app6090264
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发表时间：
2016-09-01
影响因子：
2.7
通讯作者：
Galbiati, Marta
中科院分区：
文献类型：
--
作者：
Manas-Valero, Samuel;Garcia-Lopez, Victor;Galbiati, Marta
在二维电子和光电子器件的竞赛中，来自第VIB族的半导体过渡金属二硫属化物（TMDC）由于从体材料到单层材料的间接到直接的带隙转变而近年来得到了广泛的研究。然而，新材料仍需探索。例如，已经预测来自IVB族的半导体TMDC在单层极限中具有比来自VIB族的对应物更大的迁移率。在这项工作中，我们报告的机械剥离的ZrX 2（X = S，Se）从散装到单层，我们研究了在环境条件下的拉曼光谱的维数依赖性。我们观察到拉曼信号从体层到几层，当降低维数时没有发现峰位置的移动。虽然对于ZrS2，可以从本体到双层观察到拉曼信号，但是对于ZrSe 2的薄片，我们只能检测到低至五层的信号。这些结果表明，通过机械剥离获得原子级薄层的ZrX2的可能性，并代表对这些材料的性能的调查，仍然未探索的二维极限的第一步之一。
In the race towards two-dimensional electronic and optoelectronic devices, semiconducting transition metal dichalcogenides (TMDCs) from group VIB have been intensively studied in recent years due to the indirect to direct band-gap transition from bulk to the monolayer. However, new materials still need to be explored. For example, semiconducting TMDCs from group IVB have been predicted to have larger mobilities than their counterparts from group VIB in the monolayer limit. In this work we report the mechanical exfoliation of ZrX2 (X = S, Se) from bulk down to the monolayer and we study the dimensionality dependence of the Raman spectra in ambient conditions. We observe Raman signal from bulk to few layers and no shift in the peak positions is found when decreasing the dimensionality. While a Raman signal can be observed from bulk to a bilayer for ZrS2, we could only detect signal down to five layers for flakes of ZrSe2. These results show the possibility of obtaining atomically thin layers of ZrX2 by mechanical exfoliation and represent one of the first steps towards the investigation of the properties of these materials, still unexplored in the two-dimensional limit.