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Carbon-assisted growth and high visible-light optical reflectivity of amorphous silicon oxynitride nanowires.

Zhang L, Shi T, Tang Z, Liu D, Xi S, Li X, Lai W - Nanoscale Res Lett (2011)

Bottom Line: The obtained nanowires were attractive for their exceptional whiteness, perceived brightness, and optical brilliance.These nanowires display greatly enhanced reflection over the whole visible wavelength, with more than 80% of light reflected on most of the wavelength ranging from 400 to 700 nm and the lowest reflectivity exceeding 70%, exhibiting performance superior to that of the reported white beetle.Intense visible photoluminescence is also observed over a broad spectrum ranging from 320 to 500 nm with two shoulders centered at around 444 and 468 nm, respectively.

View Article: PubMed Central - HTML - PubMed

Affiliation: Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China. zirong@mail.hust.edu.cn.

ABSTRACT
Large amounts of amorphous silicon oxynitride nanowires have been synthesized on silicon wafer through carbon-assisted vapor-solid growth avoiding the contamination from metallic catalysts. These nanowires have the length of up to 100 μm, with a diameter ranging from 50 to 150 nm. Around 3-nm-sized nanostructures are observed to be homogeneously distributed within a nanowire cross-section matrix. The unique configuration might determine the growth of ternary amorphous structure and its special splitting behavior. Optical properties of the nanowires have also been investigated. The obtained nanowires were attractive for their exceptional whiteness, perceived brightness, and optical brilliance. These nanowires display greatly enhanced reflection over the whole visible wavelength, with more than 80% of light reflected on most of the wavelength ranging from 400 to 700 nm and the lowest reflectivity exceeding 70%, exhibiting performance superior to that of the reported white beetle. Intense visible photoluminescence is also observed over a broad spectrum ranging from 320 to 500 nm with two shoulders centered at around 444 and 468 nm, respectively.

No MeSH data available.


The optical reflectivity and PL spectra of Si-O-N nanowires. (a) Reflectivity of Si-O-N nanowire mat and its comparison with literature data of human milk tooth and Cyphochilus beetle scale [17]. (b) Room temperature PL spectra of Si-O-N nanowires, using a 258-nm line of a Xe lamp as the excitation.
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Figure 5: The optical reflectivity and PL spectra of Si-O-N nanowires. (a) Reflectivity of Si-O-N nanowire mat and its comparison with literature data of human milk tooth and Cyphochilus beetle scale [17]. (b) Room temperature PL spectra of Si-O-N nanowires, using a 258-nm line of a Xe lamp as the excitation.

Mentions: Finally, the optical reflectivity of the obtained Si-O-N nanowire mat in a visible wavelength from 400 to 700 nm was characterized by Datacolor Elrepho photospectrometer, and the result is compared with ultrabright white beetle scale and human milk tooth reported in literature [20]. As shown in Figure 5a, the optical reflectivity of the Si-O-N nanowires is around 80%, while white beetle has an optical reflectivity around 65%. The excellent optical reflectivity of these nanowires is mainly due to scattering of the disordered nanowires. Furthermore, the wide distribution of the 3-nm dark spot in the nanowire leads to the inhomogeneous distribution of refractive index in the nanowire, which may affect the interaction of the incident light with the nanowire and enhance the scattering efficiency. This material may provide a number of potential applications, from cosmetic dopant and white surface for dental implants to energy-saving flat light panels, which need ultrathin reflective backings to scatter the backward light. It will also offer a permeable, flexible, and fault-tolerant layer for diffuse reflector cup, which is in great need for high-power white light-emitting diode (LED) lamps to reduce the optical loss and hence to increase the device efficiency.


Carbon-assisted growth and high visible-light optical reflectivity of amorphous silicon oxynitride nanowires.

Zhang L, Shi T, Tang Z, Liu D, Xi S, Li X, Lai W - Nanoscale Res Lett (2011)

The optical reflectivity and PL spectra of Si-O-N nanowires. (a) Reflectivity of Si-O-N nanowire mat and its comparison with literature data of human milk tooth and Cyphochilus beetle scale [17]. (b) Room temperature PL spectra of Si-O-N nanowires, using a 258-nm line of a Xe lamp as the excitation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211981&req=5

Figure 5: The optical reflectivity and PL spectra of Si-O-N nanowires. (a) Reflectivity of Si-O-N nanowire mat and its comparison with literature data of human milk tooth and Cyphochilus beetle scale [17]. (b) Room temperature PL spectra of Si-O-N nanowires, using a 258-nm line of a Xe lamp as the excitation.
Mentions: Finally, the optical reflectivity of the obtained Si-O-N nanowire mat in a visible wavelength from 400 to 700 nm was characterized by Datacolor Elrepho photospectrometer, and the result is compared with ultrabright white beetle scale and human milk tooth reported in literature [20]. As shown in Figure 5a, the optical reflectivity of the Si-O-N nanowires is around 80%, while white beetle has an optical reflectivity around 65%. The excellent optical reflectivity of these nanowires is mainly due to scattering of the disordered nanowires. Furthermore, the wide distribution of the 3-nm dark spot in the nanowire leads to the inhomogeneous distribution of refractive index in the nanowire, which may affect the interaction of the incident light with the nanowire and enhance the scattering efficiency. This material may provide a number of potential applications, from cosmetic dopant and white surface for dental implants to energy-saving flat light panels, which need ultrathin reflective backings to scatter the backward light. It will also offer a permeable, flexible, and fault-tolerant layer for diffuse reflector cup, which is in great need for high-power white light-emitting diode (LED) lamps to reduce the optical loss and hence to increase the device efficiency.

Bottom Line: The obtained nanowires were attractive for their exceptional whiteness, perceived brightness, and optical brilliance.These nanowires display greatly enhanced reflection over the whole visible wavelength, with more than 80% of light reflected on most of the wavelength ranging from 400 to 700 nm and the lowest reflectivity exceeding 70%, exhibiting performance superior to that of the reported white beetle.Intense visible photoluminescence is also observed over a broad spectrum ranging from 320 to 500 nm with two shoulders centered at around 444 and 468 nm, respectively.

View Article: PubMed Central - HTML - PubMed

Affiliation: Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China. zirong@mail.hust.edu.cn.

ABSTRACT
Large amounts of amorphous silicon oxynitride nanowires have been synthesized on silicon wafer through carbon-assisted vapor-solid growth avoiding the contamination from metallic catalysts. These nanowires have the length of up to 100 μm, with a diameter ranging from 50 to 150 nm. Around 3-nm-sized nanostructures are observed to be homogeneously distributed within a nanowire cross-section matrix. The unique configuration might determine the growth of ternary amorphous structure and its special splitting behavior. Optical properties of the nanowires have also been investigated. The obtained nanowires were attractive for their exceptional whiteness, perceived brightness, and optical brilliance. These nanowires display greatly enhanced reflection over the whole visible wavelength, with more than 80% of light reflected on most of the wavelength ranging from 400 to 700 nm and the lowest reflectivity exceeding 70%, exhibiting performance superior to that of the reported white beetle. Intense visible photoluminescence is also observed over a broad spectrum ranging from 320 to 500 nm with two shoulders centered at around 444 and 468 nm, respectively.

No MeSH data available.