| 1. |
- Hou, Yuanyuan, et al.
(författare)
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Photoluminescence properties of high-pressure-polymerized C60 nanorods in the orthorhombic and tetragonal phases.
- 2006
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 89:18, s. 181925-
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Tidskriftsartikel (refereegranskat)abstract
- C60nanorods in two polymeric phases have been synthesized under differenthigh pressure and high temperature conditions. Orthorhombic and tetragonal phaseshave been identified from Raman spectra. The rod shape canbe kept under quasihydrostatic pressure. The photoluminescence intensity of thepolymeric C60 nanorods has been greatly enhanced compared with thatof pristine C60 nanorods. The main fluorescence band shifted from730 nm in the unpolymeric phase to 748 nm and near infrared780 nm in the orthorhombic and tetragonal phases, respectively. The enhancedphotoluminescence with tunable frequency for different polymeric C60 nanorods suggestspotential applications in luminescent nanomaterials.
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| 2. |
- Wang, Lin, et al.
(författare)
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Highly Enhanced Luminescence from Single-Crystalline C60·1m-xylene Nanorods
- 2006
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Ingår i: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 18:17, s. 4190-4194
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Tidskriftsartikel (refereegranskat)abstract
- Single-crystalline C60â1m-xylene nanorods with a hexagonal structure were successfully synthesizedby evaporating a C60 solution in m-xylene at room temperature. The ratio of the length to the diameterof the nanorods can be controlled in the range of 10 to over 1000 for different applications. Thephotoluminescence (PL) intensity of the nanorods is about 2 orders of magnitude higher than that forpristine C60 crystals in air. Both UV and Raman results indicate that there is no charge transfer betweenC60 and m-xylene. It was found that the interaction between C60 and m-xylene molecules is of the vander Waals type. This interaction reduces the icosahedral symmetry of C60 molecule and induces strongPL from the solvate nanorods.
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| 3. |
- Wang, Lin, et al.
(författare)
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Synthesis of thin, rectangular C60 nanorods using m-xylene as shape controller
- 2006
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Ingår i: Advanced Materials. - : Wiley Interscience. - 0935-9648 .- 1521-4095. ; 18:14, s. 1883-1888
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Tidskriftsartikel (refereegranskat)abstract
- Thin, rectangular C60 nanorods in face-centered cubic structure are synthesized by using m-xylene as a shape controller. These unusual nanorods can easily grow on various substrates. The smallest nanorods have widths smaller than 30 nm. The nanorods are highly crystalline in single phase. A significant expansion of the lattice constant is also found in the C60 nanorods when their widths decrease below about 80 nm.
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| 4. |
- Yao, Mingguang, et al.
(författare)
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Effect of rare-earth component of the RE/Ni catalyst on the formation and nanostructure of single-walled carbon nanotubes
- 2006
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Ingår i: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1520-6106 .- 1520-5207. ; 110:31, s. 15284-15290
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Tidskriftsartikel (refereegranskat)abstract
- A systematic experimental study has been carried out on the efficiency of bimetallic catalysts based on Ni and the rare-earth elements Y, La, Ce, Nd, Gd, Tb, Dy, Ho, Er, and Lu ( group A) and Eu, Sm, Yb, and Tm ( group B) in the synthesis of single-walled carbon nanotubes (SWNTs). The two groups give quite different results when analyzed by a combination of SEM/TEM and Raman and UV-NIR spectroscopies. The elements in group A have an obvious catalytic effect and increase the yield of SWNTs dramatically, whereas those in group B are not efficient catalysts. The diameter distribution of the synthesized SWNTs was also affected by the rare-earth element used. For group A metals, there is a tendency that the fraction of small-diameter tubes decreases with decreasing ionic radius of the rare-earth element used. EDX and X-ray analyses indicate that group A metals deposit on the cathode deposits and form rare-earth carbides, whereas no group B metals are found in cathode deposits, except for a small amount of Tm present in the form of thulium carbide. Further analysis indicates that there is a very strong correlation between the ability to form rare-earth carbides and the catalytic efficiency for the formation of SWNTs.
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| 5. |
- Yao, Mingguang, et al.
(författare)
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Synthesis and characterization of SWCNTs with Ho/Ni as catalyst
- 2006
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Ingår i: New Carbon Materials. - 1007-8827. ; 21:1, s. 70-74
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Tidskriftsartikel (refereegranskat)abstract
- SWCNTs were synthesized with high yield by DC arc discharge using Ho/Ni as catalysts. The morphologies, diameter distribution and the content of SWCNTs in the products were characterized by SEM, Raman scattering and TGA. Results indicate that SWCNTs can be efficiently synthesized with Ho/Ni as catalysts. The volume content of SWCNTs in a "web-like" form is as high as 80% in the product. Furthermore, the diameter distribution of SWCNTs, estimated by analyzing the resonance Raman scattering using excitation wavelengths of 632 and 488nm, varies from 1.35 to 1.69nm with a dominant diameter of 1.5nm, which is different from that of the SWCNTs synthesized with Ce/Ni as catalyst, proving that the diameter distribution of SWCNTs is dependent on the properties of the metal catalysts.
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