Photoluminescence Enhancement and Structure Repairing of Monolayer MoSe 2 by Hydrohalic Acid Treatment
KAUST DepartmentPhysical Sciences and Engineering (PSE) Division
Permanent link to this recordhttp://hdl.handle.net/10754/596857
MetadataShow full item record
AbstractAtomically thin two-dimensional transition-metal dichalcogenides (TMDCs) have attracted much attention recently due to their unique electronic and optical properties for future optoelectronic devices. The chemical vapor deposition (CVD) method is able to generate TMDCs layers with a scalable size and a controllable thickness. However, the TMDC monolayers grown by CVD may incorporate structural defects, and it is fundamentally important to understand the relation between photoluminescence and structural defects. In this report, point defects (Se vacancies) and oxidized Se defects in CVD-grown MoSe2 monolayers are identified by transmission electron microscopy and X-ray photoelectron spectroscopy. These defects can significantly trap free charge carriers and localize excitons, leading to the smearing of free band-to-band exciton emission. Here, we report that the simple hydrohalic acid treatment (such as HBr) is able to efficiently suppress the trap-state emission and promote the neutral exciton and trion emission in defective MoSe2 monolayers through the p-doping process, where the overall photoluminescence intensity at room temperature can be enhanced by a factor of 30. We show that HBr treatment is able to activate distinctive trion and free exciton emissions even from highly defective MoSe2 layers. Our results suggest that the HBr treatment not only reduces the n-doping in MoSe2 but also reduces the structural defects. The results provide further insights of the control and tailoring the exciton emission from CVD-grown monolayer TMDCs.
CitationPhotoluminescence Enhancement and Structure Repairing of Monolayer MoSe 2 by Hydrohalic Acid Treatment 2016, 10 (1):1454 ACS Nano
PublisherAmerican Chemical Society (ACS)
- Monolayer MoSe2 grown by chemical vapor deposition for fast photodetection.
- Authors: Chang YH, Zhang W, Zhu Y, Han Y, Pu J, Chang JK, Hsu WT, Huang JK, Hsu CL, Chiu MH, Takenobu T, Li H, Wu CI, Chang WH, Wee AT, Li LJ
- Issue date: 2014 Aug 26
- Chemical vapor deposition growth of crystalline monolayer MoSe2.
- Authors: Wang X, Gong Y, Shi G, Chow WL, Keyshar K, Ye G, Vajtai R, Lou J, Liu Z, Ringe E, Tay BK, Ajayan PM
- Issue date: 2014 May 27
- Modulating Optoelectronic Properties of Two-Dimensional Transition Metal Dichalcogenide Semiconductors by Photoinduced Charge Transfer.
- Authors: Choi J, Zhang H, Choi JH
- Issue date: 2016 Jan 26
- Growth and Optical Properties of High-Quality Monolayer WS2 on Graphite.
- Authors: Kobayashi Y, Sasaki S, Mori S, Hibino H, Liu Z, Watanabe K, Taniguchi T, Suenaga K, Maniwa Y, Miyata Y
- Issue date: 2015 Apr 28
- Efficient Defect Healing of Transition Metal Dichalcogenides by Metallophthalocyanine.
- Authors: Ahn H, Huang YC, Lin CW, Chiu YL, Lin EC, Lai YY, Lee YH
- Issue date: 2018 Aug 29