Materials
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2019
·Vol. 12
·期 12
·1883
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IF 2.972
Zhuhua Xu,Yanfei Lv,Feng Huang,Cong Zhao,Shichao Zhao,Guodan Wei
Monolayer tungsten disulfide (2D WS2) films have attracted tremendous interest due to their unique electronic and optoelectronic properties. However, the controlled growth of monolayer WS2is still challenging. In this paper, we report a novel method to grow WS2through chemical vapor deposition (CVD) with ZnO crystalline whisker as a growth promoter, where partially evaporated WS2reacts with ZnO to form ZnWO4by-product. As a result, a depletion region of W atoms and S-rich region is formed which is favorable for subsequent monolayer growth of WS2, selectively positioned on the silicon oxide substrate after the CVD growth.Keywords:monolayer WS2;ZnO;CVD;controlled growth
研究领域:
材料科学
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纳米技术
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DOI
PubMed
高影响因子
Materials Research Express
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2019
·Vol. 6
·期 11
·115084
·
IF 1.449
Feng Huang,Yanfei Lv,Siwei Zhang,Guodan Wei,Shichao Zhao
Monolayer Tungsten disulfide (WS2) shows unique optoelectronic properties and has potential applications in nanodevices. However, the stability of the monolayer WS2 exposed in the ambient condition should be evaluated and improved before its practical application. In this paper, we investigated the shape, structure, and luminescence of the monolayer WS2 under heating and corona discharge conditions in air. We show that monolayer WS2 without any coating film is unstable under such practical condition. To protect the monolayer, we covered a layer of polymethyl methacrylate (PMMA) on the surface of the monolayer WS2 and found the stability was improved.
研究领域:
材料科学
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物理化学
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DOI
高影响因子
Journal of Physical Chemistry C
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2023
·
IF 3.7
Maomiao Xiang,Jun Fu,Chenxi Huang,Yue Xing,Jiefu Zhang,Hualing Zeng,Xiang Shao
Monolayer transition-metal dichalcogenides (TMDs) have registered attractive potential applications in optoelectronics, spintronics, and valleytronics. Here, we develop a simple chemical vapor deposition method to directly grow large-size monolayer WS2 on an atomically flat rutile TiO2(110) substrate. The variety of microscopic and spectroscopic characterizations reveals the highly single crystallinity of the as-grown WS2 and the atomically clean WS2/TiO2 interface. Such structural perfection renders a neutral excitonic photoluminescence of WS2 with extremely small spectral broadening of around 20 meV at cryogenic temperature. Moreover, the low concentration of defect leads to the suppressed intervalley scattering, while the efficient interfacial electron transfer reduces the Coulomb interaction between the valleys of the WS2, which thus enhance the valley polarization and coherence significantly so that it can reserve up to room temperature under ambient conditions. These results demonstrate that the substrate tuning corroborated by interface control can be a promising strategy to utilize the TMDs in practical valleytronics.
研究领域:
材料科学
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凝聚态物理
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光学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Xiaojie Wei,Chengbin Liu,Hehe Qin,Ziwei Ye,Xinru Liu,Boyang Zong,Zhuo Li,Shun Mao
Antibiotic residues cause increasing concern in environmental ecology and public health, which needs efficient analysis strategy for monitoring and control. In this study, a fast, specific, and ultrasensitive sensor based on field-effect transistor (FET) has been proposed for the detection of ampicillin (AMP). The sensor involves monolayer tungsten disulfide (WS 2 ) nanosheet as the sensing channel, single-stranded DNA (ssDNA) as the sensing probe, and gold nanoparticle (Au NP) as the linker. The WS 2 /Au/ssDNA FET sensor responds rapidly to AMP in a wide linear detection range (10 −12 –10 −6 M) and has low limit of detection (0.556 pM), which meets the permissible standards of AMP in water and food. The sensing mechanism study suggests that the excellent sensor response results from the increased number of negative charges in the Debye length and the consequent accumulation of holes in WS 2 channel after the addition of AMP. Moreover, satisfactory sensing performance was confirmed in real water samples, indicating the potential application of the proposed method in practical AMP detection. The reported FET sensing strategy provides new insights in antibiotic analysis for risk assessment and control.
研究领域:
环境科学
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生物医学工程
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DOI
PubMed
高影响因子
Polymers
·
2023
·Vol. 15
·期 13
·2791
·
IF 5
Mingqiang Shao,Yiran Shi,Jiangtao Liu,Baoxia Xue,Mei Niu
Improving the residual char of polypropylene (PP) is difficult due to the preferential complete combustion. Here, we designed a combination catalyst that not only provides physical barrier effects, but also dramatically promotes catalytic charring activity. We successfully synthesized WS2monolayer sheets decorated with isolated Ni atoms that bond covalently to sulfur vacancies on the basal planes via thiourea. Subsequently, PP blends composed of 8 wt.% Ni-decorated WS2, NiO, and activated carbon (AC) were obtained (ENi-SWS2-AC-PP). Combining the physical barrier effects of WS2monolayer sheets with the excellent catalytic carbonization ability of theENi-SWS2-AC combination catalyst, the PP blends showed a remarkable improvement in flame retardancy, with the yield of residual char reaching as high as 41.6 wt.%. According to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations, it was revealed that the microstructure of residual char contained a large number of carbon nanotubes. The production of a large amount of residual char not only reduced the release of pyrolytic products, but also formed a thermal shield preventing oxygen and heat transport. Compared to pure PP, the peak heat release rate (pHRR) and total heat release rate (THR) ofENi-SWS2-AC-PP were reduced by 46.32% and 26.03%, respectively. Furthermore, benefiting from the highly dispersed WS2, the tensile strength and Young’s modulus ofENi-SWS2-AC-PP showed similar values to pure PP, without sacrificing the toughness.Keywords:polypropylene;Ni-modified monolayer WS2;sulfur vacancy;activated carbon;NiO;carbon nanotubes;flame retardancy;mechanical properties
研究领域:
材料科学
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化学工程
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DOI
PubMed
高影响因子
Frontiers in Materials
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2021
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IF 3.515
Wen Shiya,Deng Shiyu,Chen Kun,Chen Huanjun,Deng Shaozhi
Resonance coupling between plasmonic resonances in metallic nanostructures and excitons in two-dimensional (2D) semiconductors has attracted much recent attention. The 2D semiconductor excitons are sensitive to external stimulus, enabling active tuning on the resonance couplings by physical, such as applying electrostatic gating, thermal scanning, etc., or chemical approaches. Among the others, chemical tuning approach has the advantage of facile implementation, high efficiency, and being capable of large-area tuning. Here, we report on chemical tuning of resonance coupling in heterostructures consisted of individual gold nanorods integrated with monolayer WS2. We showed that by incubating the heterostructures into a bis (trifluoro-methane) sulfonimide (TFSI) solution, the exciton transition strength of the WS2 will be enhanced significantly. As a result, the resonance coupling in the heterostructures evolved from a weak coupling regime to a strong coupling one, with the mode splitting energy increases from 94.96 to 105.32 meV. These findings highlight the potential of chemical treatment as an efficient technique for tailoring the interactions between plasmonic nanostructures and 2D semiconductors.
研究领域:
材料科学
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纳米技术
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光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
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