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Great blue-shift of luminescence of ZnO nanoparticle array constructed from ZnO quantum dots.

Wang N, Yang Y, Yang G - Nanoscale Res Lett (2011)

Bottom Line: The cathodoluminescence measurements showed that there is a pronounced blue-shift of luminescence comparable to those of the bulk counterpart, which is suggested to originate from ZnO QDs with small size where the quantum confinement effect can work well.The fabrication mechanism of the ZnO nanoparticle array constructed from ZnO QDs was proposed, in which the immiscible-like interaction between ZnO nuclei and Si surface play a key role in the ZnO QDs cluster formation.These investigations showed the fabricated nanostructure has potential applications in ultraviolet emitters.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, Institute of Optoelectronic and Functional Composite Materials, Nanotechnology Research Center, School of Physics & Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, P, R, China. stsygw@mail.sysu.edu.cn.

ABSTRACT
ZnO nanoparticle array has been fabricated on the Si substrate by a simple thermal chemical vapor transport and condensation without any metal catalysts. This ZnO nanoparticles array is constructed from ZnO quantum dots (QDs), and half-embedded in the amorphous silicon oxide layer on the surface of the Si substrate. The cathodoluminescence measurements showed that there is a pronounced blue-shift of luminescence comparable to those of the bulk counterpart, which is suggested to originate from ZnO QDs with small size where the quantum confinement effect can work well. The fabrication mechanism of the ZnO nanoparticle array constructed from ZnO QDs was proposed, in which the immiscible-like interaction between ZnO nuclei and Si surface play a key role in the ZnO QDs cluster formation. These investigations showed the fabricated nanostructure has potential applications in ultraviolet emitters.

No MeSH data available.


Related in: MedlinePlus

The TEM and EELS analysis of the structure details of the sample. TEM image with the inserted FFT pattern of the sample in a large area (a), HRTEM image with a highlighted ZnO nanoparticle and the corresponding interplanar spacing (b), EELS of the Zn-L edge (c), O-K edge (d), and Si-L edge (e).
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Figure 2: The TEM and EELS analysis of the structure details of the sample. TEM image with the inserted FFT pattern of the sample in a large area (a), HRTEM image with a highlighted ZnO nanoparticle and the corresponding interplanar spacing (b), EELS of the Zn-L edge (c), O-K edge (d), and Si-L edge (e).

Mentions: In order to verify the detailed structure of the fabricated nanoparticle array, we prepare the cross-sectional sample for TEM characterization, and the results are shown in Figure 2. In the low magnification of TEM image in Figure 2a, the thickness of the layer is uniform of approx. 25 nm, while two high contrast particles are implanted in the layer. The sizes of the two particles are, respectively, 50 and 57 nm at the interface. The FFT pattern (the inset of Figure 2a) of one particle indicates that it is polycrystalline. The HRTEM image in Figure 2b is taken from the upper ZnO nanoparticle in Figure 2a. Clearly, we can see that several small crystalline particles gather together and form one nanoparticle. The average size of these small ZnO particles is 5.5 nm, which are the so-called ZnO QDs [4-13]. One ZnO QD has been emphasized and marked with the interplanar spacing of 0.265 nm in the inset of Figure 2b, which is corresponding to the plane (002) of the wurtzite ZnO. Actually, all the interplanar spacings of QDs in Figure 2b and other HRTEM data can be assigned to the spacings of the wurtzite ZnO structure. In addition, we can easily observe that these ZnO QDs are embedded in the amorphous silicon oxide layer on the surface of the Si substrate. Therefore, these results show that the fabricated ZnO nanoparticle array is constructed from ZnO QDs.


Great blue-shift of luminescence of ZnO nanoparticle array constructed from ZnO quantum dots.

Wang N, Yang Y, Yang G - Nanoscale Res Lett (2011)

The TEM and EELS analysis of the structure details of the sample. TEM image with the inserted FFT pattern of the sample in a large area (a), HRTEM image with a highlighted ZnO nanoparticle and the corresponding interplanar spacing (b), EELS of the Zn-L edge (c), O-K edge (d), and Si-L edge (e).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211426&req=5

Figure 2: The TEM and EELS analysis of the structure details of the sample. TEM image with the inserted FFT pattern of the sample in a large area (a), HRTEM image with a highlighted ZnO nanoparticle and the corresponding interplanar spacing (b), EELS of the Zn-L edge (c), O-K edge (d), and Si-L edge (e).
Mentions: In order to verify the detailed structure of the fabricated nanoparticle array, we prepare the cross-sectional sample for TEM characterization, and the results are shown in Figure 2. In the low magnification of TEM image in Figure 2a, the thickness of the layer is uniform of approx. 25 nm, while two high contrast particles are implanted in the layer. The sizes of the two particles are, respectively, 50 and 57 nm at the interface. The FFT pattern (the inset of Figure 2a) of one particle indicates that it is polycrystalline. The HRTEM image in Figure 2b is taken from the upper ZnO nanoparticle in Figure 2a. Clearly, we can see that several small crystalline particles gather together and form one nanoparticle. The average size of these small ZnO particles is 5.5 nm, which are the so-called ZnO QDs [4-13]. One ZnO QD has been emphasized and marked with the interplanar spacing of 0.265 nm in the inset of Figure 2b, which is corresponding to the plane (002) of the wurtzite ZnO. Actually, all the interplanar spacings of QDs in Figure 2b and other HRTEM data can be assigned to the spacings of the wurtzite ZnO structure. In addition, we can easily observe that these ZnO QDs are embedded in the amorphous silicon oxide layer on the surface of the Si substrate. Therefore, these results show that the fabricated ZnO nanoparticle array is constructed from ZnO QDs.

Bottom Line: The cathodoluminescence measurements showed that there is a pronounced blue-shift of luminescence comparable to those of the bulk counterpart, which is suggested to originate from ZnO QDs with small size where the quantum confinement effect can work well.The fabrication mechanism of the ZnO nanoparticle array constructed from ZnO QDs was proposed, in which the immiscible-like interaction between ZnO nuclei and Si surface play a key role in the ZnO QDs cluster formation.These investigations showed the fabricated nanostructure has potential applications in ultraviolet emitters.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, Institute of Optoelectronic and Functional Composite Materials, Nanotechnology Research Center, School of Physics & Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, P, R, China. stsygw@mail.sysu.edu.cn.

ABSTRACT
ZnO nanoparticle array has been fabricated on the Si substrate by a simple thermal chemical vapor transport and condensation without any metal catalysts. This ZnO nanoparticles array is constructed from ZnO quantum dots (QDs), and half-embedded in the amorphous silicon oxide layer on the surface of the Si substrate. The cathodoluminescence measurements showed that there is a pronounced blue-shift of luminescence comparable to those of the bulk counterpart, which is suggested to originate from ZnO QDs with small size where the quantum confinement effect can work well. The fabrication mechanism of the ZnO nanoparticle array constructed from ZnO QDs was proposed, in which the immiscible-like interaction between ZnO nuclei and Si surface play a key role in the ZnO QDs cluster formation. These investigations showed the fabricated nanostructure has potential applications in ultraviolet emitters.

No MeSH data available.


Related in: MedlinePlus