WO3 nanowires were fabricated by a hydrothermal method,which proceeded at 170 ℃ for 48 h in a solution containing C2H10N6H2SO4 as a dispersant and Na2WO4 as a starting material.The nanowires exhibit a well crystalliz...WO3 nanowires were fabricated by a hydrothermal method,which proceeded at 170 ℃ for 48 h in a solution containing C2H10N6H2SO4 as a dispersant and Na2WO4 as a starting material.The nanowires exhibit a well crystallized one-dimensional structure with 20 nm in diameter and several microns in length.The physicochemical properties of WO3 were compared using X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,energy dispersive X-ray spectroscopy（EDX） and UV-vis spectroscopy（UV-Vis）.The photoactivity of the as-perpared WO3 nanowires was evaluated through the photodegradation of methylene blue（MB） in aqueous solution.The experimental results demonstrate that addition of C2H10N6H2SO4 salt in the WO3 nanowires synthesis process can enhance its photocatalytic activity obviously.展开更多
In this Letter, the effects of material/structure parameters of photonic crystal（Ph C） parallel waveguides on the coupling length are investigated. The results show that, increasing the effective relative permittivi...In this Letter, the effects of material/structure parameters of photonic crystal（Ph C） parallel waveguides on the coupling length are investigated. The results show that, increasing the effective relative permittivity of the Ph C leads to a downward shift of the photonic bandgap and a variation of the coupling length. A compact Ph C 1.31/1.55 μm wavelength division multiplexer（WDM）/demultiplexer with simple structure is proposed,where the output power ratios are more than 24 d B. This WDM can multiplex/demultiplex other light waves efficiently.展开更多
Tadpole-shaped Au nano-particles with controllable tails are successfully fabricated by simply using laser fragmentation of separated Au nano-spheres in liquid. The optimum laser power densities（1.5–3 GW∕cm-2） can...Tadpole-shaped Au nano-particles with controllable tails are successfully fabricated by simply using laser fragmentation of separated Au nano-spheres in liquid. The optimum laser power densities（1.5–3 GW∕cm-2） can enable part of the individual Au nano-sphere to be re-melted, released, and ultra-rapidly recondensed/crystallized on the outside of the original region. We find that the length of the tail in a tadpole-shaped Au nano-particle significantly increases from about 10 to 25 nm by increasing the laser power density. Benefiting from the unique structural features, the localized surface plasmon resonance（LSPR） absorption spectra of the tadpole-shaped Au nano-particles become broader by increasing the tail length. Moreover, the LSPR absorption band also exhibits a noticeable red shift from about 520 to 650 nm. Our results provide a convenient and valuable strategy to fabricated novel anisotropic-shaped nano-structures with fascinating properties.展开更多
基金Funded by the National Natural Science Foundation of China(No.21501159)
文摘WO3 nanowires were fabricated by a hydrothermal method,which proceeded at 170 ℃ for 48 h in a solution containing C2H10N6H2SO4 as a dispersant and Na2WO4 as a starting material.The nanowires exhibit a well crystallized one-dimensional structure with 20 nm in diameter and several microns in length.The physicochemical properties of WO3 were compared using X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,energy dispersive X-ray spectroscopy（EDX） and UV-vis spectroscopy（UV-Vis）.The photoactivity of the as-perpared WO3 nanowires was evaluated through the photodegradation of methylene blue（MB） in aqueous solution.The experimental results demonstrate that addition of C2H10N6H2SO4 salt in the WO3 nanowires synthesis process can enhance its photocatalytic activity obviously.
基金supported by the National Natural Science Foundation of China(No.61405058)the Hunan Provincial Natural Science Foundation of China(No.2017JJ2048)the Fundamental Research Funds for the Central Universities(No.531107050979)
文摘In this Letter, the effects of material/structure parameters of photonic crystal（Ph C） parallel waveguides on the coupling length are investigated. The results show that, increasing the effective relative permittivity of the Ph C leads to a downward shift of the photonic bandgap and a variation of the coupling length. A compact Ph C 1.31/1.55 μm wavelength division multiplexer（WDM）/demultiplexer with simple structure is proposed,where the output power ratios are more than 24 d B. This WDM can multiplex/demultiplex other light waves efficiently.
基金supported by the National Natural Science Foundation of China(Nos.11575102,11105085,and 11375108)the Fundamental Research Funds of Shandong University,China(No.2015JC007)
文摘Tadpole-shaped Au nano-particles with controllable tails are successfully fabricated by simply using laser fragmentation of separated Au nano-spheres in liquid. The optimum laser power densities（1.5–3 GW∕cm-2） can enable part of the individual Au nano-sphere to be re-melted, released, and ultra-rapidly recondensed/crystallized on the outside of the original region. We find that the length of the tail in a tadpole-shaped Au nano-particle significantly increases from about 10 to 25 nm by increasing the laser power density. Benefiting from the unique structural features, the localized surface plasmon resonance（LSPR） absorption spectra of the tadpole-shaped Au nano-particles become broader by increasing the tail length. Moreover, the LSPR absorption band also exhibits a noticeable red shift from about 520 to 650 nm. Our results provide a convenient and valuable strategy to fabricated novel anisotropic-shaped nano-structures with fascinating properties.
