Abstract

To tune the electronic and optoelectronic properties of graphene quantum dots (GQDs), heteroatom doping (e.g., nitrogen (N), boron (B), and sulfur (S)) is an effective method. However, it is difficult to incorporate S into the carbon framework of GQDs because the atomic size of S is much larger than that of C atoms, compared to N and B. In this study, we report a simple and one-step method for the synthesis of sulfur-doped GQDs (S-GQDs) via the pulsed laser ablation in liquid (PLAL) process. The as-prepared S-GQDs exhibited enhanced fluorescence quantum yields (0.8% → 3.89%) with a huge improved absorption band in ultraviolet (UV) region (200 ∼ 400 nm) and excellent photo stability under the UV radiation at 360 nm. In addition, XPS results revealed that the PLAL process can effectively facilitate the incorporation of S into the carbon framework compared to those produced by the chemical exfoliation method (e.g., hydrothermal method). And also, the mechanisms related with the optical properties of S-GQDs was investigated by time-resolved photoluminescence (TRPL) spectroscopy. We believe that the PLAL process proposed in this study will serve as a simple and one-step route for designing S-GQDs and opens up to opportunities for their potential applications.

© 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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  3. G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
    [Crossref]
  4. X. Sun, Z. Liu, K. Welsher, J. T. Robinson, A. Goodwin, S. Zaric, and H. Dai, “Nano-Graphene Oxide for Cellular Imaging and Drug Delivery,” Nano Res. 1(3), 203–212 (2008).
    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]
  19. D. Zhang, B. Gokce, and S. Barcikowski, “Laser Synthesis and Processing of Colloids: Fundamentals and Applications,” Chem. Rev. 117(5), 3990–4103 (2017).
    [Crossref]
  20. S. Kang, S. Mhin, H. Han, K. M. Kim, J. L. Jones, J. H. Ryu, J. S. Kang, S. H. Kim, and K. B. Shim, “Ultrafast method for selective design of graphene quantum dots with highly efficient blue emission,” Sci. Rep. 6(1), 38423 (2016).
    [Crossref]
  21. Z. Yan and D. B. Chrisey, “Pulsed laser ablation in liquid for micro-/nanostructure generation,” J. Photochem. Photobiol., C 13(3), 204–223 (2012).
    [Crossref]
  22. V. Amendola and M. Meneghetti, “What controls the composition and the structure of nanomaterials generated by laser ablation in liquid solution?” Phys. Chem. Chem. Phys. 15(9), 3027–3046 (2013).
    [Crossref]
  23. S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
    [Crossref]
  24. S. Kang, K. M. Kim, K. Jung, Y. Son, S. Mhin, J. H. Ryu, K. B. Shim, B. Lee, H. Han, and T. Song, “Graphene oxide quantum dots derived from coal for bioimaging: facile and green approach,” Sci. Rep. 9(1), 4101 (2019).
    [Crossref]
  25. S. Zhu, J. Zhang, S. Tang, C. Qiao, L. Wang, H. Wang, X. Liu, B. Li, Y. Li, W. Yu, X. Wang, H. Sun, and B. Yang, “Surface chemistry routes to modulate the photoluminescence of graphene quantum dots: from fluorescence mechanism to up-conversion bio imaging applications,” Adv. Funct. Mater. 22(22), 4732–4740 (2012).
    [Crossref]
  26. L. Wang, Y. Wang, T. Xu, H. Liao, C. Yao, Y. Liu, Z. Li, Z. Chen, D. Pan, L. Sun, and M. Wu, “Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties,” Nat. Commun. 5(1), 5357 (2014).
    [Crossref]
  27. W. Kichiski, M. Szala, and M. Bystrzejewski, “Sulfur doped porous carbon: Synthesis and applications,” Carbon 68, 1–32 (2014).
    [Crossref]
  28. H. L. Tran and R. Doong, “Sustainable fabrication of green luminescence sulfur-doped graphene quantum dots for rapid visual detection of hemoglobin,” Anal. Methods 11(35), 4421–4430 (2019).
    [Crossref]
  29. S. Lai, Y. Jin, L. Shi, R. Zhou, Y. Zhou, and D. An, “Mechanisms behind excitation- and concentration-dependent multicolor photoluminescence in graphene quantum dots,” Nanoscale 12(2), 591–601 (2020).
    [Crossref]
  30. Z. Gan, H. Xu, and Y. Hao, “Mechanism for excitation-dependent photoluminescence from graphene quantum dots and other graphene oxide derivates: consensus, debates and challenges,” Nanoscale 8(15), 7794–7807 (2016).
    [Crossref]
  31. J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
    [Crossref]
  32. R. Riaz, M. Ali, T. Maiyalagan, A. S. Anjum, S. Lee, M. J. Ko, and S. H. Jeong, “Dye-sensitized solar cell (DSSC) coated with energy down shift layer of nitrogen-doped carbon quantum dots (N-CQDs) for enhanced current density and stability,” Appl. Surf. Sci. 483(31), 425–431 (2019).
    [Crossref]
  33. F. Liu, M. H. Jang, H. D. Ha, J. H. Kim, Y. H. Cho, and T. S. Seo, “Facile synthetic method for pristine graphene quantum dots and graphene oxide quantum dots: origins of blue and green luminescence,” Adv. Mater. 25(27), 3657–3662 (2013).
    [Crossref]

2020 (2)

S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
[Crossref]

S. Lai, Y. Jin, L. Shi, R. Zhou, Y. Zhou, and D. An, “Mechanisms behind excitation- and concentration-dependent multicolor photoluminescence in graphene quantum dots,” Nanoscale 12(2), 591–601 (2020).
[Crossref]

2019 (5)

J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
[Crossref]

R. Riaz, M. Ali, T. Maiyalagan, A. S. Anjum, S. Lee, M. J. Ko, and S. H. Jeong, “Dye-sensitized solar cell (DSSC) coated with energy down shift layer of nitrogen-doped carbon quantum dots (N-CQDs) for enhanced current density and stability,” Appl. Surf. Sci. 483(31), 425–431 (2019).
[Crossref]

H. L. Tran and R. Doong, “Sustainable fabrication of green luminescence sulfur-doped graphene quantum dots for rapid visual detection of hemoglobin,” Anal. Methods 11(35), 4421–4430 (2019).
[Crossref]

S. Kang, K. M. Kim, K. Jung, Y. Son, S. Mhin, J. H. Ryu, K. B. Shim, B. Lee, H. Han, and T. Song, “Graphene oxide quantum dots derived from coal for bioimaging: facile and green approach,” Sci. Rep. 9(1), 4101 (2019).
[Crossref]

S. Kadian, G. Manik, A. KalKal, M. Singh, and R. P. Chauhan, “Effect of sulfur doping on fluorescence and quantum yield of graphene quantum dots: an experimental and theoretical investigation,” Nanotechnology 30(43), 435704 (2019).
[Crossref]

2018 (2)

G. Yang, C. Wu, X. Luo, X. Liu, Y. Gao, P. Wu, C. Cai, and S. S. Saavedra, “Exploring the emissive states of heteroatom-doped Graphene Quantum Dots,” J. Phys. Chem. C 122(11), 6483–6492 (2018).
[Crossref]

B. Huang, J. He, S. Bian, C. Zhou, Z. Li, F. Xi, J. Liu, and X. Dong, “S-doped graphene quantum dots as nanophotocatalyst for visible light degradation,” Chin. Chem. Lett. 29(11), 1698–1701 (2018).
[Crossref]

2017 (1)

D. Zhang, B. Gokce, and S. Barcikowski, “Laser Synthesis and Processing of Colloids: Fundamentals and Applications,” Chem. Rev. 117(5), 3990–4103 (2017).
[Crossref]

2016 (3)

S. Kang, S. Mhin, H. Han, K. M. Kim, J. L. Jones, J. H. Ryu, J. S. Kang, S. H. Kim, and K. B. Shim, “Ultrafast method for selective design of graphene quantum dots with highly efficient blue emission,” Sci. Rep. 6(1), 38423 (2016).
[Crossref]

Z. Gan, H. Xu, and Y. Hao, “Mechanism for excitation-dependent photoluminescence from graphene quantum dots and other graphene oxide derivates: consensus, debates and challenges,” Nanoscale 8(15), 7794–7807 (2016).
[Crossref]

S. Bian, C. Shen, H. Hua, L. Zhou, H. Zhu, F. Xi, J. Liu, and X. Dong, “One-pot synthesis of sulfur-doped graphene quantum dots as a novel fluorescent probe for highly selective and sensitive detection of lead(ii),” RSC Adv. 6(74), 69977–69983 (2016).
[Crossref]

2015 (1)

X. Li, M. Rui, J. Song, Z. Shen, and H. Zeng, “Carbon and Graphene quantum dots for optoelectronic and energy devices: A Review,” Adv. Funct. Mater. 25(31), 4929–4947 (2015).
[Crossref]

2014 (6)

L. Wang, Y. Wang, T. Xu, H. Liao, C. Yao, Y. Liu, Z. Li, Z. Chen, D. Pan, L. Sun, and M. Wu, “Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties,” Nat. Commun. 5(1), 5357 (2014).
[Crossref]

W. Kichiski, M. Szala, and M. Bystrzejewski, “Sulfur doped porous carbon: Synthesis and applications,” Carbon 68, 1–32 (2014).
[Crossref]

M. Bacon, S. J. Bradley, and T. Nann, “Graphene Quantum Dots,” Part. Part. Syst. Charact. 31(4), 415–428 (2014).
[Crossref]

X. Wang, G. Sun, P. Routh, D. H. Kim, W. Huang, and P. Chem, “Heteroatom-doped graphene materials: syntheses, properties and applications,” Chem. Soc. Rev. 43(20), 7067–7098 (2014).
[Crossref]

S. Li, Y. Li, J. Cao, J. Zhu, L. Fan, and X. Li, “Sulfur-doped graphene quantum dots as a novel fluorescent prove for highly selective and sensitive detection of Fe3+,” Anal. Chem. 86(20), 10201–10207 (2014).
[Crossref]

Z. Fan, Y. Li, X. Li, L. Fan, S. Zhou, D. Fang, and S. Yang, “Surrounding media sensitive photoluminescence of boron-doped graphene quantum dots for highly fluorescent dyed crystals, chemical sensing and bioimaging,” Carbon 70, 149–156 (2014).
[Crossref]

2013 (7)

D. Qu, M. Zheng, P. Du, Y. Zhou, L. Zhang, D. Li, H. Tan, Z. Zhao, Z. Xie, and Z. Sun, “Highly luminescent S, N co-doped graphene quantum dots with broad visible absorption bands for visible light photocatalysts,” Nanoscale 5(24), 12272–12277 (2013).
[Crossref]

C. Hu, Y. Liu, Y. Yang, J. Cui, Z. Huang, Y. Wang, L. Yang, H. Wang, Y. Xiao, and J. Rong, “One-step preparation of nitrogen-doped graphene quantum dots from oxidized debris of graphene oxide,” J. Mater. Chem. B 1(1), 39–42 (2013).
[Crossref]

Q. Liu, B. Guo, Z. Rao, B. Zhang, and J. R. Gong, “Strong Two-photon-Induced Fluorescence from photostable, Biocompatible Nitrogen-Doped Graphene Quantum Dots for Cellular and Deep-Tissue Imaging,” Nano Lett. 13(6), 2436–2441 (2013).
[Crossref]

S. Chandra, P. Patra, S. H. Pathan, S. Roy, S. Mitra, A. Layek, R. Bhar, P. Pramanik, and A. Goswami, “Luminescent S-doped carbon dots: an emergent architecture for multimodal applications,” J. Mater. Chem. B 1(18), 2375–2382 (2013).
[Crossref]

L. Tang, R. Ji, X. Li, K. S. Teng, and S. P. Lau, “Energy-level structure of nitrogen-doped graphene quantum dots,” J. Mater. Chem. C 1(32), 4908 (2013).
[Crossref]

F. Liu, M. H. Jang, H. D. Ha, J. H. Kim, Y. H. Cho, and T. S. Seo, “Facile synthetic method for pristine graphene quantum dots and graphene oxide quantum dots: origins of blue and green luminescence,” Adv. Mater. 25(27), 3657–3662 (2013).
[Crossref]

V. Amendola and M. Meneghetti, “What controls the composition and the structure of nanomaterials generated by laser ablation in liquid solution?” Phys. Chem. Chem. Phys. 15(9), 3027–3046 (2013).
[Crossref]

2012 (3)

S. Zhu, J. Zhang, S. Tang, C. Qiao, L. Wang, H. Wang, X. Liu, B. Li, Y. Li, W. Yu, X. Wang, H. Sun, and B. Yang, “Surface chemistry routes to modulate the photoluminescence of graphene quantum dots: from fluorescence mechanism to up-conversion bio imaging applications,” Adv. Funct. Mater. 22(22), 4732–4740 (2012).
[Crossref]

Z. Yan and D. B. Chrisey, “Pulsed laser ablation in liquid for micro-/nanostructure generation,” J. Photochem. Photobiol., C 13(3), 204–223 (2012).
[Crossref]

Y. Li, Y. Zhao, H. Cheng, Y. Hu, G. Shi, L. Dai, and L. Qu, “Nitrogen-Doped Graphene Quantum Dots with Oxygen-Rich Functional Groups,” J. Am. Chem. Soc. 134(1), 15–18 (2012).
[Crossref]

2010 (1)

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[Crossref]

2009 (1)

K. A. Ritter and J. W. Lyding, “The influence of edge structure on the electronic properties of graphene quantum dots and nanoribbons,” Nat. Mater. 8(3), 235–242 (2009).
[Crossref]

2008 (1)

X. Sun, Z. Liu, K. Welsher, J. T. Robinson, A. Goodwin, S. Zaric, and H. Dai, “Nano-Graphene Oxide for Cellular Imaging and Drug Delivery,” Nano Res. 1(3), 203–212 (2008).
[Crossref]

Ali, M.

R. Riaz, M. Ali, T. Maiyalagan, A. S. Anjum, S. Lee, M. J. Ko, and S. H. Jeong, “Dye-sensitized solar cell (DSSC) coated with energy down shift layer of nitrogen-doped carbon quantum dots (N-CQDs) for enhanced current density and stability,” Appl. Surf. Sci. 483(31), 425–431 (2019).
[Crossref]

Amendola, V.

V. Amendola and M. Meneghetti, “What controls the composition and the structure of nanomaterials generated by laser ablation in liquid solution?” Phys. Chem. Chem. Phys. 15(9), 3027–3046 (2013).
[Crossref]

An, D.

S. Lai, Y. Jin, L. Shi, R. Zhou, Y. Zhou, and D. An, “Mechanisms behind excitation- and concentration-dependent multicolor photoluminescence in graphene quantum dots,” Nanoscale 12(2), 591–601 (2020).
[Crossref]

Anjum, A. S.

R. Riaz, M. Ali, T. Maiyalagan, A. S. Anjum, S. Lee, M. J. Ko, and S. H. Jeong, “Dye-sensitized solar cell (DSSC) coated with energy down shift layer of nitrogen-doped carbon quantum dots (N-CQDs) for enhanced current density and stability,” Appl. Surf. Sci. 483(31), 425–431 (2019).
[Crossref]

Bacon, M.

M. Bacon, S. J. Bradley, and T. Nann, “Graphene Quantum Dots,” Part. Part. Syst. Charact. 31(4), 415–428 (2014).
[Crossref]

Barcikowski, S.

D. Zhang, B. Gokce, and S. Barcikowski, “Laser Synthesis and Processing of Colloids: Fundamentals and Applications,” Chem. Rev. 117(5), 3990–4103 (2017).
[Crossref]

Bhar, R.

S. Chandra, P. Patra, S. H. Pathan, S. Roy, S. Mitra, A. Layek, R. Bhar, P. Pramanik, and A. Goswami, “Luminescent S-doped carbon dots: an emergent architecture for multimodal applications,” J. Mater. Chem. B 1(18), 2375–2382 (2013).
[Crossref]

Bian, S.

B. Huang, J. He, S. Bian, C. Zhou, Z. Li, F. Xi, J. Liu, and X. Dong, “S-doped graphene quantum dots as nanophotocatalyst for visible light degradation,” Chin. Chem. Lett. 29(11), 1698–1701 (2018).
[Crossref]

S. Bian, C. Shen, H. Hua, L. Zhou, H. Zhu, F. Xi, J. Liu, and X. Dong, “One-pot synthesis of sulfur-doped graphene quantum dots as a novel fluorescent probe for highly selective and sensitive detection of lead(ii),” RSC Adv. 6(74), 69977–69983 (2016).
[Crossref]

Bradley, S. J.

M. Bacon, S. J. Bradley, and T. Nann, “Graphene Quantum Dots,” Part. Part. Syst. Charact. 31(4), 415–428 (2014).
[Crossref]

Bystrzejewski, M.

W. Kichiski, M. Szala, and M. Bystrzejewski, “Sulfur doped porous carbon: Synthesis and applications,” Carbon 68, 1–32 (2014).
[Crossref]

Cai, C.

G. Yang, C. Wu, X. Luo, X. Liu, Y. Gao, P. Wu, C. Cai, and S. S. Saavedra, “Exploring the emissive states of heteroatom-doped Graphene Quantum Dots,” J. Phys. Chem. C 122(11), 6483–6492 (2018).
[Crossref]

Cao, J.

S. Li, Y. Li, J. Cao, J. Zhu, L. Fan, and X. Li, “Sulfur-doped graphene quantum dots as a novel fluorescent prove for highly selective and sensitive detection of Fe3+,” Anal. Chem. 86(20), 10201–10207 (2014).
[Crossref]

Chandra, S.

S. Chandra, P. Patra, S. H. Pathan, S. Roy, S. Mitra, A. Layek, R. Bhar, P. Pramanik, and A. Goswami, “Luminescent S-doped carbon dots: an emergent architecture for multimodal applications,” J. Mater. Chem. B 1(18), 2375–2382 (2013).
[Crossref]

Chauhan, R. P.

S. Kadian, G. Manik, A. KalKal, M. Singh, and R. P. Chauhan, “Effect of sulfur doping on fluorescence and quantum yield of graphene quantum dots: an experimental and theoretical investigation,” Nanotechnology 30(43), 435704 (2019).
[Crossref]

Chem, P.

X. Wang, G. Sun, P. Routh, D. H. Kim, W. Huang, and P. Chem, “Heteroatom-doped graphene materials: syntheses, properties and applications,” Chem. Soc. Rev. 43(20), 7067–7098 (2014).
[Crossref]

Chen, C. W.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[Crossref]

Chen, H. A.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[Crossref]

Chen, I. S.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[Crossref]

Chen, Z.

L. Wang, Y. Wang, T. Xu, H. Liao, C. Yao, Y. Liu, Z. Li, Z. Chen, D. Pan, L. Sun, and M. Wu, “Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties,” Nat. Commun. 5(1), 5357 (2014).
[Crossref]

Cheng, H.

Y. Li, Y. Zhao, H. Cheng, Y. Hu, G. Shi, L. Dai, and L. Qu, “Nitrogen-Doped Graphene Quantum Dots with Oxygen-Rich Functional Groups,” J. Am. Chem. Soc. 134(1), 15–18 (2012).
[Crossref]

Chhowalla, M.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
[Crossref]

Cho, M.

J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
[Crossref]

Cho, Y. H.

F. Liu, M. H. Jang, H. D. Ha, J. H. Kim, Y. H. Cho, and T. S. Seo, “Facile synthetic method for pristine graphene quantum dots and graphene oxide quantum dots: origins of blue and green luminescence,” Adv. Mater. 25(27), 3657–3662 (2013).
[Crossref]

Chrisey, D. B.

Z. Yan and D. B. Chrisey, “Pulsed laser ablation in liquid for micro-/nanostructure generation,” J. Photochem. Photobiol., C 13(3), 204–223 (2012).
[Crossref]

Cui, J.

C. Hu, Y. Liu, Y. Yang, J. Cui, Z. Huang, Y. Wang, L. Yang, H. Wang, Y. Xiao, and J. Rong, “One-step preparation of nitrogen-doped graphene quantum dots from oxidized debris of graphene oxide,” J. Mater. Chem. B 1(1), 39–42 (2013).
[Crossref]

Dai, H.

X. Sun, Z. Liu, K. Welsher, J. T. Robinson, A. Goodwin, S. Zaric, and H. Dai, “Nano-Graphene Oxide for Cellular Imaging and Drug Delivery,” Nano Res. 1(3), 203–212 (2008).
[Crossref]

Dai, L.

Y. Li, Y. Zhao, H. Cheng, Y. Hu, G. Shi, L. Dai, and L. Qu, “Nitrogen-Doped Graphene Quantum Dots with Oxygen-Rich Functional Groups,” J. Am. Chem. Soc. 134(1), 15–18 (2012).
[Crossref]

Dong, X.

B. Huang, J. He, S. Bian, C. Zhou, Z. Li, F. Xi, J. Liu, and X. Dong, “S-doped graphene quantum dots as nanophotocatalyst for visible light degradation,” Chin. Chem. Lett. 29(11), 1698–1701 (2018).
[Crossref]

S. Bian, C. Shen, H. Hua, L. Zhou, H. Zhu, F. Xi, J. Liu, and X. Dong, “One-pot synthesis of sulfur-doped graphene quantum dots as a novel fluorescent probe for highly selective and sensitive detection of lead(ii),” RSC Adv. 6(74), 69977–69983 (2016).
[Crossref]

Doong, R.

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J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
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B. Huang, J. He, S. Bian, C. Zhou, Z. Li, F. Xi, J. Liu, and X. Dong, “S-doped graphene quantum dots as nanophotocatalyst for visible light degradation,” Chin. Chem. Lett. 29(11), 1698–1701 (2018).
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S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
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S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
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S. Kang, K. M. Kim, K. Jung, Y. Son, S. Mhin, J. H. Ryu, K. B. Shim, B. Lee, H. Han, and T. Song, “Graphene oxide quantum dots derived from coal for bioimaging: facile and green approach,” Sci. Rep. 9(1), 4101 (2019).
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F. Liu, M. H. Jang, H. D. Ha, J. H. Kim, Y. H. Cho, and T. S. Seo, “Facile synthetic method for pristine graphene quantum dots and graphene oxide quantum dots: origins of blue and green luminescence,” Adv. Mater. 25(27), 3657–3662 (2013).
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J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
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S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
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S. Kang, S. Mhin, H. Han, K. M. Kim, J. L. Jones, J. H. Ryu, J. S. Kang, S. H. Kim, and K. B. Shim, “Ultrafast method for selective design of graphene quantum dots with highly efficient blue emission,” Sci. Rep. 6(1), 38423 (2016).
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S. Kang, S. Mhin, H. Han, K. M. Kim, J. L. Jones, J. H. Ryu, J. S. Kang, S. H. Kim, and K. B. Shim, “Ultrafast method for selective design of graphene quantum dots with highly efficient blue emission,” Sci. Rep. 6(1), 38423 (2016).
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S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
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J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
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J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
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S. Lai, Y. Jin, L. Shi, R. Zhou, Y. Zhou, and D. An, “Mechanisms behind excitation- and concentration-dependent multicolor photoluminescence in graphene quantum dots,” Nanoscale 12(2), 591–601 (2020).
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L. Tang, R. Ji, X. Li, K. S. Teng, and S. P. Lau, “Energy-level structure of nitrogen-doped graphene quantum dots,” J. Mater. Chem. C 1(32), 4908 (2013).
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S. Chandra, P. Patra, S. H. Pathan, S. Roy, S. Mitra, A. Layek, R. Bhar, P. Pramanik, and A. Goswami, “Luminescent S-doped carbon dots: an emergent architecture for multimodal applications,” J. Mater. Chem. B 1(18), 2375–2382 (2013).
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S. Kang, Y. K. Jeong, J. H. Ryu, Y. Son, W. R. Kim, B. Lee, K. H. Jung, and K. M. Kim, “Pulsed laser ablation based synthetic route for nitrogen-doped graphene quantum dots using graphite flakes,” Appl. Surf. Sci. 506(15), 144998 (2020).
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S. Kang, K. M. Kim, K. Jung, Y. Son, S. Mhin, J. H. Ryu, K. B. Shim, B. Lee, H. Han, and T. Song, “Graphene oxide quantum dots derived from coal for bioimaging: facile and green approach,” Sci. Rep. 9(1), 4101 (2019).
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J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
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R. Riaz, M. Ali, T. Maiyalagan, A. S. Anjum, S. Lee, M. J. Ko, and S. H. Jeong, “Dye-sensitized solar cell (DSSC) coated with energy down shift layer of nitrogen-doped carbon quantum dots (N-CQDs) for enhanced current density and stability,” Appl. Surf. Sci. 483(31), 425–431 (2019).
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J. H. Lee, S. H. Kwon, S. Kwon, M. Cho, K. H. Kim, T. H. Han, and S. G. Lee, “Tunable Electronic properties of Nitrogen and sulfur doped graphene: Density Functional Theory Approach,” Nanomaterials 9(2), 268 (2019).
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S. Zhu, J. Zhang, S. Tang, C. Qiao, L. Wang, H. Wang, X. Liu, B. Li, Y. Li, W. Yu, X. Wang, H. Sun, and B. Yang, “Surface chemistry routes to modulate the photoluminescence of graphene quantum dots: from fluorescence mechanism to up-conversion bio imaging applications,” Adv. Funct. Mater. 22(22), 4732–4740 (2012).
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D. Qu, M. Zheng, P. Du, Y. Zhou, L. Zhang, D. Li, H. Tan, Z. Zhao, Z. Xie, and Z. Sun, “Highly luminescent S, N co-doped graphene quantum dots with broad visible absorption bands for visible light photocatalysts,” Nanoscale 5(24), 12272–12277 (2013).
[Crossref]

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S. Li, Y. Li, J. Cao, J. Zhu, L. Fan, and X. Li, “Sulfur-doped graphene quantum dots as a novel fluorescent prove for highly selective and sensitive detection of Fe3+,” Anal. Chem. 86(20), 10201–10207 (2014).
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S. Li, Y. Li, J. Cao, J. Zhu, L. Fan, and X. Li, “Sulfur-doped graphene quantum dots as a novel fluorescent prove for highly selective and sensitive detection of Fe3+,” Anal. Chem. 86(20), 10201–10207 (2014).
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Z. Fan, Y. Li, X. Li, L. Fan, S. Zhou, D. Fang, and S. Yang, “Surrounding media sensitive photoluminescence of boron-doped graphene quantum dots for highly fluorescent dyed crystals, chemical sensing and bioimaging,” Carbon 70, 149–156 (2014).
[Crossref]

L. Tang, R. Ji, X. Li, K. S. Teng, and S. P. Lau, “Energy-level structure of nitrogen-doped graphene quantum dots,” J. Mater. Chem. C 1(32), 4908 (2013).
[Crossref]

Li, Y.

Z. Fan, Y. Li, X. Li, L. Fan, S. Zhou, D. Fang, and S. Yang, “Surrounding media sensitive photoluminescence of boron-doped graphene quantum dots for highly fluorescent dyed crystals, chemical sensing and bioimaging,” Carbon 70, 149–156 (2014).
[Crossref]

S. Li, Y. Li, J. Cao, J. Zhu, L. Fan, and X. Li, “Sulfur-doped graphene quantum dots as a novel fluorescent prove for highly selective and sensitive detection of Fe3+,” Anal. Chem. 86(20), 10201–10207 (2014).
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Y. Li, Y. Zhao, H. Cheng, Y. Hu, G. Shi, L. Dai, and L. Qu, “Nitrogen-Doped Graphene Quantum Dots with Oxygen-Rich Functional Groups,” J. Am. Chem. Soc. 134(1), 15–18 (2012).
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S. Zhu, J. Zhang, S. Tang, C. Qiao, L. Wang, H. Wang, X. Liu, B. Li, Y. Li, W. Yu, X. Wang, H. Sun, and B. Yang, “Surface chemistry routes to modulate the photoluminescence of graphene quantum dots: from fluorescence mechanism to up-conversion bio imaging applications,” Adv. Funct. Mater. 22(22), 4732–4740 (2012).
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Li, Z.

B. Huang, J. He, S. Bian, C. Zhou, Z. Li, F. Xi, J. Liu, and X. Dong, “S-doped graphene quantum dots as nanophotocatalyst for visible light degradation,” Chin. Chem. Lett. 29(11), 1698–1701 (2018).
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L. Wang, Y. Wang, T. Xu, H. Liao, C. Yao, Y. Liu, Z. Li, Z. Chen, D. Pan, L. Sun, and M. Wu, “Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties,” Nat. Commun. 5(1), 5357 (2014).
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G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
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F. Liu, M. H. Jang, H. D. Ha, J. H. Kim, Y. H. Cho, and T. S. Seo, “Facile synthetic method for pristine graphene quantum dots and graphene oxide quantum dots: origins of blue and green luminescence,” Adv. Mater. 25(27), 3657–3662 (2013).
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Liu, J.

B. Huang, J. He, S. Bian, C. Zhou, Z. Li, F. Xi, J. Liu, and X. Dong, “S-doped graphene quantum dots as nanophotocatalyst for visible light degradation,” Chin. Chem. Lett. 29(11), 1698–1701 (2018).
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S. Bian, C. Shen, H. Hua, L. Zhou, H. Zhu, F. Xi, J. Liu, and X. Dong, “One-pot synthesis of sulfur-doped graphene quantum dots as a novel fluorescent probe for highly selective and sensitive detection of lead(ii),” RSC Adv. 6(74), 69977–69983 (2016).
[Crossref]

Liu, Q.

Q. Liu, B. Guo, Z. Rao, B. Zhang, and J. R. Gong, “Strong Two-photon-Induced Fluorescence from photostable, Biocompatible Nitrogen-Doped Graphene Quantum Dots for Cellular and Deep-Tissue Imaging,” Nano Lett. 13(6), 2436–2441 (2013).
[Crossref]

Liu, X.

G. Yang, C. Wu, X. Luo, X. Liu, Y. Gao, P. Wu, C. Cai, and S. S. Saavedra, “Exploring the emissive states of heteroatom-doped Graphene Quantum Dots,” J. Phys. Chem. C 122(11), 6483–6492 (2018).
[Crossref]

S. Zhu, J. Zhang, S. Tang, C. Qiao, L. Wang, H. Wang, X. Liu, B. Li, Y. Li, W. Yu, X. Wang, H. Sun, and B. Yang, “Surface chemistry routes to modulate the photoluminescence of graphene quantum dots: from fluorescence mechanism to up-conversion bio imaging applications,” Adv. Funct. Mater. 22(22), 4732–4740 (2012).
[Crossref]

Liu, Y.

L. Wang, Y. Wang, T. Xu, H. Liao, C. Yao, Y. Liu, Z. Li, Z. Chen, D. Pan, L. Sun, and M. Wu, “Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties,” Nat. Commun. 5(1), 5357 (2014).
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C. Hu, Y. Liu, Y. Yang, J. Cui, Z. Huang, Y. Wang, L. Yang, H. Wang, Y. Xiao, and J. Rong, “One-step preparation of nitrogen-doped graphene quantum dots from oxidized debris of graphene oxide,” J. Mater. Chem. B 1(1), 39–42 (2013).
[Crossref]

Liu, Z.

X. Sun, Z. Liu, K. Welsher, J. T. Robinson, A. Goodwin, S. Zaric, and H. Dai, “Nano-Graphene Oxide for Cellular Imaging and Drug Delivery,” Nano Res. 1(3), 203–212 (2008).
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G. Yang, C. Wu, X. Luo, X. Liu, Y. Gao, P. Wu, C. Cai, and S. S. Saavedra, “Exploring the emissive states of heteroatom-doped Graphene Quantum Dots,” J. Phys. Chem. C 122(11), 6483–6492 (2018).
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R. Riaz, M. Ali, T. Maiyalagan, A. S. Anjum, S. Lee, M. J. Ko, and S. H. Jeong, “Dye-sensitized solar cell (DSSC) coated with energy down shift layer of nitrogen-doped carbon quantum dots (N-CQDs) for enhanced current density and stability,” Appl. Surf. Sci. 483(31), 425–431 (2019).
[Crossref]

Manik, G.

S. Kadian, G. Manik, A. KalKal, M. Singh, and R. P. Chauhan, “Effect of sulfur doping on fluorescence and quantum yield of graphene quantum dots: an experimental and theoretical investigation,” Nanotechnology 30(43), 435704 (2019).
[Crossref]

Mattevi, C.

G. Eda, Y. Y. Lin, C. Mattevi, H. Yamaguchi, H. A. Chen, I. S. Chen, C. W. Chen, and M. Chhowalla, “Blue photoluminescence from chemically derived graphene oxide,” Adv. Mater. 22(4), 505–509 (2010).
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S. Kang, K. M. Kim, K. Jung, Y. Son, S. Mhin, J. H. Ryu, K. B. Shim, B. Lee, H. Han, and T. Song, “Graphene oxide quantum dots derived from coal for bioimaging: facile and green approach,” Sci. Rep. 9(1), 4101 (2019).
[Crossref]

S. Kang, S. Mhin, H. Han, K. M. Kim, J. L. Jones, J. H. Ryu, J. S. Kang, S. H. Kim, and K. B. Shim, “Ultrafast method for selective design of graphene quantum dots with highly efficient blue emission,” Sci. Rep. 6(1), 38423 (2016).
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Adv. Funct. Mater. (2)

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Figures (7)

Fig. 1.
Fig. 1. Representation schematic for the possible mechanisms of the transformation of graphite to S-GQDs by the PLAL process.
Fig. 2.
Fig. 2. TEM images of S-GQDs: (a) S5-GQDs, (c) S10-GQDs, and (e) S15-GQDs. HR-TEM images of S-GQDs: (b) S5-GQDs, (d) S10-GQDs, and (f) S15-GQDs. Insets are the FFT pattern (left), which shows the high-quality crystalline hexagonal patterns of the GQDs. Right side insets show the lattice distance of the S-GQDs.
Fig. 3.
Fig. 3. AFM images and insets are height distribution of (a) PGQDs, (b) S5-GQDs, (c) S-10GQDs, and (d) S15-GQDs.
Fig. 4.
Fig. 4. Optical properties of PGQDs, S5-GQDs, S10-GQDs, and S15-GQDs. (a) Photoluminescence (PL) properties under 360 nm excitation, (b) PL excitation, (c) Uv-vis spectra, and (d) Dependence of PL emission spectra on UV excitation time for S10-GQDs
Fig. 5.
Fig. 5. Structural analysis of S-GQDs. (a) XPS full-survey spectra of PGQDs, S5-GQDs, S10-GQDs, and S15-GQDs. XPS C1s spectra of (b) S10-GQDs and S2p spectra of the (c) S10-GQDs. (d) Dependence of the S doping concentration and quantum yield of the S-GQDs on the MPA concentration.
Fig. 6.
Fig. 6. XPS spectra of (a,b) S5-GQDs and (c,d) S15-GQDs.
Fig. 7.
Fig. 7. TCSPC decay curves of the (a) PGQDs, (b) S5-GQDs, (c) S10-GQDs, and (d) S15-GQDs. The solid line (red line) is fitted by a tri-exponential function.

Tables (1)

Tables Icon

Table 1. Excitation emission values, χ2 values, excitation lifetimes, and their corresponding amplitudes for PGQDs, S5-GQDs, S10-GQDs, and S15-GQDs.

Equations (2)

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Φ x = Φ st ( I x / I st ) ( η x 2 / η st 2 ) ( A st / A x )
fit = A +  B 1 e ( - t/ τ 1)  +  B 2 e ( - t/ τ 2)  +  B 3 e ( - t/ τ 3)

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