Confocal absorption spectral imaging of MoS2: optical transitions   depending on the atomic thickness of intrinsic and chemically doped MoS2

doi:10.1039/c4nr03703k

CORC > 北京大学 > 工学院

	Confocal absorption spectral imaging of MoS2: optical transitions depending on the atomic thickness of intrinsic and chemically doped MoS2
	Dhakal, Krishna P. ; Dinh Loc Duong ; Lee, Jubok ; Nam, Honggi ; Kim, Minsu ; Kan, Min ; Lee, Young Hee ; Kim, Jeongyong
刊名	nanoscale
	2014
关键词	SINGLE-LAYER MOS2 MONOLAYER MOS2 RAMAN-SCATTERING METAL DICHALCOGENIDES EXFOLIATED MOS2 CHARGE-TRANSFER PHOTOLUMINESCENCE GRAPHENE VIOLOGEN DOPANTS
DOI	10.1039/c4nr03703k
英文摘要	We performed a nanoscale confocal absorption spectral imaging to obtain the full absorption spectra (over the range 1.5-3.2 eV) within regions having different numbers of layers and studied the variation of optical transition depending on the atomic thickness of the MoS2 film. Three distinct absorption bands corresponding to A and B excitons and a high-energy background (BG) peak at 2.84 eV displayed a gradual redshift as the MoS2 film thickness increased from the monolayer, to the bilayer, to the bulk MoS2 and this shift was attributed to the reduction of the gap energy in the Brillouin zone at the K-point as the atomic thickness increased. We also performed n-type chemical doping of MoS2 films using reduced benzyl viologen (BV) and the confocal absorption spectra modified by the doping showed a strong dependence on the atomic thickness: A and B exciton peaks were greatly quenched in the monolayer MoS2 while much less effect was shown in larger thickness and the BG peak either showed very small quenching for 1 L MoS2 or remained constant for larger thicknesses. Our results indicate that confocal absorption spectral imaging can provide comprehensive information on optical transitions of microscopic size intrinsic and doped two-dimensional layered materials.; Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; SCI(E); EI; 5; ARTICLE; j.kim@skku.edu; 21; 13028-13035; 6
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/217437]
专题	工学院
推荐引用方式 GB/T 7714	Dhakal, Krishna P.,Dinh Loc Duong,Lee, Jubok,et al. Confocal absorption spectral imaging of MoS2: optical transitions depending on the atomic thickness of intrinsic and chemically doped MoS2[J]. nanoscale,2014.
APA	Dhakal, Krishna P..,Dinh Loc Duong.,Lee, Jubok.,Nam, Honggi.,Kim, Minsu.,...&Kim, Jeongyong.(2014).Confocal absorption spectral imaging of MoS2: optical transitions depending on the atomic thickness of intrinsic and chemically doped MoS2.nanoscale.
MLA	Dhakal, Krishna P.,et al."Confocal absorption spectral imaging of MoS2: optical transitions depending on the atomic thickness of intrinsic and chemically doped MoS2".nanoscale (2014).