ACS Applied Materials & Interfaces
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2017
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IF 7.504
Xiaoshuang Chen,Yunfeng Qiu,Huihui Yang,Guangbo Liu,Wei Zheng,Wei Feng,Wenwu Cao,Wenping Hu,PingAn Hu
Considering the unique layered structure and novel optoelectronic properties of individual MoS2 and MoSe2, as well as the quantum coherence or donor–acceptor coupling effects between these two components, rational design and artificial growth of in-plane mosaic MoS2/MoSe2 lateral heterojunctions film on conventional amorphous SiO2/Si substrate are in high demand. In this article, large-area, uniform, high-quality mosaic MoS2/MoSe2 lateral heterojunctions film was successfully grown on SiO2/Si substrate for the first time by chemical vapor deposition (CVD) technique. MoSe2 film was grown along MoS2 triangle edges and occupied the blanks of the substrate, finally leading to the formation of mosaic MoS2/MoSe2 lateral heterojunctions film. The composition and microstructure of mosaic MoS2/MoSe2 lateral heterojunctions film were characterized by various analytic techniques. Photodetectors based on mosaic MoS2/MoSe2 lateral heterojunctions film, triangular MoS2 monolayer, and multilayer MoSe2 film are systematically investigated. The mosaic MoS2/MoSe2 lateral heterojunctions film photodetector exhibited optimal photoresponse performance, giving rise to responsivity, detectivity, and external quantum efficiency (EQE) up to 1.3 A W–1, 2.6 × 1011 Jones, and 263.1%, respectively, under the bias voltage of 5 V with 0.29 mW cm–2 (610 nm), possibly due to the matched band alignment of MoS2 and MoSe2 and strong donor–acceptor delocalization effect between them. Taking into account the similar edge conditions of transition metal dichalcogenides (TMDCs), such a facile and reliable approach might open up a unique route for preparing other 2D mosaic lateral heterojunctions films in a manipulative manner. Furthermore, the mosaic lateral heterojunctions film like MoS2/MoSe2 in the present work will be a promising candidate for optoelectronic fields.
研究领域:
材料科学
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纳米技术
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光电子学
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半导体物理
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薄膜生长
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2021
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IF 5.097
Pengtao Tang,Haibo Shu,Mingjun Yang,Mingsong Zhang,Chuangwei Sheng,Pei Liang,Dan Cao,Xiaoshuang Chen
Monolayer transition metal dichalcogenide (TMD) alloys with tunable band gaps exhibit huge potential in nanoelectronics, optoelectronics, and photonics. The scalable production of uniform atomically thin TMD alloys is a key step for the realization of their device applications but remains a large challenge so far. Here, we report oxygen-assisted chemical vapor deposition (CVD) of uniform atomically thin MoS2(1–x)Se2x semiconductor alloys via a vertical Mo-precursor supply strategy. The growth scheme leads to the formation of highly crystalline MoS2(1–x)Se2x monolayer films within a short growth time of 8 min, which benefits from a stable and homogeneous Mo-precursor feeding environment and the synergic effect of NaBr and oxygen carrier on the growth. The high-resolution spectral characterizations and density functional theory calculations demonstrate that the chemical composition of the as-grown MoS2(1–x)Se2x monolayers can be continuously tuned from x = 0 to 1, leading to the corresponding band gap being gradually changed from 1.81 to 1.55 eV. This work provides an efficient strategy to obtain large-area uniform MoS2(1–x)Se2x monolayer alloys with tunable compositions and optical properties, which is essential for driving their applications in various functional optoelectronic devices, especially for high-performance flexible photodetectors.
研究领域:
材料科学
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纳米电子学
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光电子学
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光子学
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半导体合金
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薄膜生长
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Junjie Jiang,Dingbang Yang,Yongsong Wang,Xiao Guo,Madoune Yassine,Wenqiang Huang,Tao Xu,Shanshan Wang,Han Huang,Fangping Ouyang,Yongli Gao
Identifying the crystallographic orientations and understanding the growth mechanism of MoO 2 nanocrystals are important for device applications. Here, we investigate the effect of precursor concentrations in chemical vapor deposition on the orientation of MoO 2 nanoflakes with respect to the substrate surface. X-ray diffraction, optical microscopy, (tilted) scanning electron microscopy, high resolution transmission electron microscopy, selected area electron diffraction, and angle-resolved polarized Raman spectroscopy were used to determine the crystal orientations of the nanoflakes and their epitaxial relationship with c- sapphire substrates: lying-down MoO 2 nanoflakes for MoO 2 (0 1 0)∥sapphire(0001) and MoO 2 <0 0 1>//sapphire< 1 1 ¯ 00 >, and standing-up ones for MoO 2 (1 0 0)∥sapphire(0001) and MoO 2 <0 0 1>∥sapphire< 1 1 ¯ 00 >. Tentative atomic epitaxial models are proposed to explain the orientation and alignment. The investigations also demonstrated that angle-resolved polarized Raman spectroscopy is a quick and nondestructive method to identify the crystallographic orientations of nanoflakes.
研究领域:
材料科学
·
纳米技术
·
晶体学
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薄膜生长
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拉曼光谱学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）