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Controllable size-selective method to prepare graphene quantum dots from graphene oxide.

Fan T, Zeng W, Tang W, Yuan C, Tong S, Cai K, Liu Y, Huang W, Min Y, Epstein AJ - Nanoscale Res Lett (2015)

Bottom Line: We demonstrated one-step method to fabricate two different sizes of graphene quantum dots (GQDs) through chemical cutting from graphene oxide (GO), which had many advantages in terms of simple process, low cost, and large scale in manufacturing with higher production yield comparing to the reported methods.Bright blue luminescent GQDs were obtained with a produced yield as high as 34.8%.Moreover, how the different sizes affect fluorescence wavelength mechanism was investigated in details.

View Article: PubMed Central - PubMed

Affiliation: Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, 9 Wenyuan Road, Nanjing, Jiangsu 210046 China.

ABSTRACT
We demonstrated one-step method to fabricate two different sizes of graphene quantum dots (GQDs) through chemical cutting from graphene oxide (GO), which had many advantages in terms of simple process, low cost, and large scale in manufacturing with higher production yield comparing to the reported methods. Several analytical methods were employed to characterize the composition and morphology of the resultants. Bright blue luminescent GQDs were obtained with a produced yield as high as 34.8%. Moreover, how the different sizes affect fluorescence wavelength mechanism was investigated in details.

No MeSH data available.


Images of the morphology of GQDs-1 and GQDs-2 by AFM. (a) AFM images of GQDs-1 at the range of 5 μm. (b) Height profile and (c) height distribution of GQDs-1. (d) AFM images of GQDs-2 at the range of 5 μm. (e) Height profile and (f) height distribution of GQDs-2.
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Fig4: Images of the morphology of GQDs-1 and GQDs-2 by AFM. (a) AFM images of GQDs-1 at the range of 5 μm. (b) Height profile and (c) height distribution of GQDs-1. (d) AFM images of GQDs-2 at the range of 5 μm. (e) Height profile and (f) height distribution of GQDs-2.

Mentions: Figure 4a, d showed those images of the morphology of GQDs-1 and GQDs-2 by atomic force microscopy (AFM). The heights of GQDs-1 were mainly distributed in the range of 2 to 4 nm with average heights of 2.4 nm as shown in Figure 4b, e, which was similar to previous reports [23,24]. However, the topographic heights of GQDs-2 were mostly between 1 and 2 nm with an average height of 1.6 nm, suggesting that most of GQDs-2 were about five layers as shown in Figure 4c, f. The dimensions and height of GQDs-2 showed no perceptible change, indicating that the PL blue shift of GQDs-2 could be attributed to their size change rather than their dimension variation. Considering the theoretical thickness of a graphene layer of 0.34 nm, the AFM data implied that about five to seven layers of monolayer nanographene sheets consisted of GQDs-1 and GQDs-2.Figure 4


Controllable size-selective method to prepare graphene quantum dots from graphene oxide.

Fan T, Zeng W, Tang W, Yuan C, Tong S, Cai K, Liu Y, Huang W, Min Y, Epstein AJ - Nanoscale Res Lett (2015)

Images of the morphology of GQDs-1 and GQDs-2 by AFM. (a) AFM images of GQDs-1 at the range of 5 μm. (b) Height profile and (c) height distribution of GQDs-1. (d) AFM images of GQDs-2 at the range of 5 μm. (e) Height profile and (f) height distribution of GQDs-2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
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getmorefigures.php?uid=PMC4385023&req=5

Fig4: Images of the morphology of GQDs-1 and GQDs-2 by AFM. (a) AFM images of GQDs-1 at the range of 5 μm. (b) Height profile and (c) height distribution of GQDs-1. (d) AFM images of GQDs-2 at the range of 5 μm. (e) Height profile and (f) height distribution of GQDs-2.
Mentions: Figure 4a, d showed those images of the morphology of GQDs-1 and GQDs-2 by atomic force microscopy (AFM). The heights of GQDs-1 were mainly distributed in the range of 2 to 4 nm with average heights of 2.4 nm as shown in Figure 4b, e, which was similar to previous reports [23,24]. However, the topographic heights of GQDs-2 were mostly between 1 and 2 nm with an average height of 1.6 nm, suggesting that most of GQDs-2 were about five layers as shown in Figure 4c, f. The dimensions and height of GQDs-2 showed no perceptible change, indicating that the PL blue shift of GQDs-2 could be attributed to their size change rather than their dimension variation. Considering the theoretical thickness of a graphene layer of 0.34 nm, the AFM data implied that about five to seven layers of monolayer nanographene sheets consisted of GQDs-1 and GQDs-2.Figure 4

Bottom Line: We demonstrated one-step method to fabricate two different sizes of graphene quantum dots (GQDs) through chemical cutting from graphene oxide (GO), which had many advantages in terms of simple process, low cost, and large scale in manufacturing with higher production yield comparing to the reported methods.Bright blue luminescent GQDs were obtained with a produced yield as high as 34.8%.Moreover, how the different sizes affect fluorescence wavelength mechanism was investigated in details.

View Article: PubMed Central - PubMed

Affiliation: Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, 9 Wenyuan Road, Nanjing, Jiangsu 210046 China.

ABSTRACT
We demonstrated one-step method to fabricate two different sizes of graphene quantum dots (GQDs) through chemical cutting from graphene oxide (GO), which had many advantages in terms of simple process, low cost, and large scale in manufacturing with higher production yield comparing to the reported methods. Several analytical methods were employed to characterize the composition and morphology of the resultants. Bright blue luminescent GQDs were obtained with a produced yield as high as 34.8%. Moreover, how the different sizes affect fluorescence wavelength mechanism was investigated in details.

No MeSH data available.