量子點因其出色的發光特性成為下一代發光材料的有力競爭者之一。本篇論文中主要討論了兩種結構的電激發量子點發光二極體，可因此分為兩部分。第一部分中通過氧化鎳電洞傳輸層，硒化鎘/硫化鋅核殼型量子點發光層，氧化鋅奈米粒子電子傳輸層來構建全無機量子點發光二極體。第二部分中使用氧化石墨烯量子點作為發光層，構建無毒性的量子點發光二極體。
本文第一部分中，首先使用溶液飛濺法將氧化鎳電洞傳輸層，硒化鎘/硫化鋅核殼型量子點發光層，氧化鋅奈米粒子電子傳輸層塗佈到氧化銦錫玻璃基板之上，最後熱蒸鍍上鋁電極來製成一種低成本的全無機發光二極體。在這一部分的第一小節之中，通過氧化鎳前驅物溶液的調製和電荷傳輸層厚度的優化，我們成功製成了最大亮度達到8868cd/m2，最大電流效率為1.27cd/A的全無機量子點發光二極體。在第一部分的第二小節中，通過改善退火時通入的氣體、退火的溫度和退火后臭氧紫外線處理的加入，所製成的全無機量子點發光二極體最大亮度從7748cd/m2上升到11713cd/m2最後到14623cd/m2，最大電流效率亦從1.16cd/A提升到1.52cd/A最後到1.66cd/A。最佳化的元件亮度超過了已刊發的世界紀錄，但效率還需要長足的進步。
本文第二部分中，成功的使用氧化石墨烯量子點作為發光層製成了無毒性的發光二極體。並且該發光二極體的發光波長會隨著注入電流的改變而改變，注入電流增大發光波長亦會增大，發光色彩會向紅光方向漂移。這一新穎的發光特性使得將來製成通過注入電流控制色彩而不是傳統的利用三原色像素來控制色彩的發光二極體成為了可能。

Quantum dots are one of the competitive candidate of the next generation of emission materials due to its excellent luminescent properties. In this thesis, two kinds of electrical operating quantum dot light emitting diodes are discussed, which can be divided into two parts. In the first part, all-inorganic QD-LEDs fabricated by NiOx hole transport layer, CdSe/ZnS@ZnS core-shell QDs emission layer and ZnO nanoparticle electron transport layer. The second part used graphene oxide quantum dots as the emission layer to fabricated the non-toxic QD-LEDs.
In the first part of this thesis, the NiOx HTL , CdSe/ZnS@ZnS emission layer and ZnO NPs ETL were all spin-coated onto the Glass/ITO substrate.And finally thermal evaporation the aluminum electrode on the top to fabricated a low-cost all-inorganic QD-LEDs. In the first part of this section, by modulation of NiOx solution and optimization of the thickness of charge transport layers, our device achieved high maximum luminance (8868cd/m2) and high maximum current efficiency (1.27cd/A). And in the second part of this section, by optimization of annealing ambient, annealing temperature and taking UV-ozone treatment into process, the luminance and efficiency of the all-inorganic QD-LEDs have been further improved. The maximum luminance increased from 7748cd/m2 to 11713cd/m2 and to the last 14623cd/m2. And maximum current efficiency increased from 1.16cd/A to 1.52cd/A and at last 1.66cd/A. The maximum luminance achieved by our devices were higher than any other published works, however, there was much room for improvement of efficiency.
In the second part of this thesis, graphene oxide quantum dots was adopted in our QD-LEDs to replace CdSe QDs to reduce the toxicity. We fabricated a light emitting diodes based on GOQDs emission layer successfully. And by applying various injection current, the color tunability in electroluminescence was observed in GOQDs device. When increasing the injection current, a red shift phenomenon can be observed in device based on GOQDs. This fancy color-shift phenomenon is essential to manufacture colorful LEDs by applying current density instead of incorporating different color pixels. In the second part of this thesis, the successful use of graphene oxide quantum dots as a emission layer made of non-toxic QD-LEDs. And the emission wavelength of the GOQDs light emitting diodes changed with the change of injection current, the injection current increase the emission wavelength increased, a red shift phenomenon happened. This novel color-shift phenomenon makes it possible to make light-emitting diodes that control colors by injecting current rather than the traditional use of three color pixels.

1. Electroluminescent Organicand Quantum Dot LEDs: The State of the Art. Journal of Display Technology,VOL.11,NO.5, 480–493 (2015)
2. Shchukin, V. A. & Bimberg, D. Spontaneous ordering of nanostructures on crystal surfaces. Rev. Mod. Phys. 71, 1125–1171 (1999).
3. Hollingsworth, J. A. & Klimov, V. I. Nanocrystal Quantum Dots 2nd edn, Ch. 1 (CRC, 2010).
4. Norris, D. J., Bawendi, M. G. & Brus, L. E. Molecular Electronics: A “Chemistry for the 21st Century” Monograph Ch. 9 (Blackwell Science, 1997).
5. Baldo, M. A. & Forrest, S. R. Highly efficient phosphorescent emission from organic electroluminescent devices. Nature 395, 151–154 (1998).
6. Zhu, T. et al. Mist fabrication of light emitting diodes with colloidal nanocrystal quantum dots. Appl. Phys. Lett. 92, 023111 (2008).
7. Haverinen, H. M., Myllylä, R. A. & Jabbour, G. E. Inkjet printing of light emitting quantum dots. Appl. Phys. Lett. 94, 073108 (2009).
8. Wood, V. et al. Inkjet-printed quantum dot-polymer composites for full-color AC-driven displays. Adv. Mater. 21, 2151–2155 (2009).
9. Kim, L. et al. Contact printing of quantum dot light-emitting devices. Nano Lett. 8, 4513–4517 (2008).
10. Kim, T.-H. et al. Full-colour quantum dot displays fabricated by transfer printing. Nature Photon. 5, 176–182 (2011).
11. van Sark, W. G. J. H. M., Frederix, P. L. T. M., Bol, A. A., Gerritsen, H. C. & Meijerink, A. Blueing, bleaching, and blinking of single CdSe/ZnS quantum dots. ChemPhysChem 3, 871–879 (2002).
12. Chen, Y. et al. ‘Giant’ multishell CdSe nanocrystal quantum dots with suppressed blinking. J. Am. Chem. Soc. 130, 5026–5027 (2008).
13. Mahler, B. et al. Towards non-blinking colloidal quantum dots. Nature Mater. 7, 659–664 (2008).
14. Hohng, S. & Ha, T. Near-complete suppression of quantum dot blinking in ambient conditions. J. Am. Chem. Soc. 126, 1324–1325 (2004).
15. Wang, X. et al. Non-blinking semiconductor nanocrystals. Nature 459, 686–689 (2009).
16. Yasuhiro Shirasaki, Geoffrey J. Supran2, Moungi G. Bawendi and Vladimir Bulović1. Emergence of colloidal quantum-dot light-emitting technologies, Nature Photonics 7, 13–23 (2013)
17. Chang, T.-W. F. et al. Efficient excitation transfer from polymer to nanocrystals. Appl. Phys. Lett. 84, 4295–4297 (2004).
18. Panzer, M. J. et al. Nanoscale morphology revealed at the interface between colloidal quantum dots and organic semiconductor films. Nano Lett. 10, 2421–2426 (2010).
19. Achermann, M., Petruska, M. A, Koleske, D. D., Crawford, M. H. & Klimov, V. I. Nanocrystal-based light-emitting diodes utilizing high-efficiency nonradiative energy transfer for color conversion. Nano Lett. 6, 1396–1400 (2006).
20. Achermann, M. et al. Energy-transfer pumping of semiconductor nanocrystals using an epitaxial quantum well. Nature 429, 642–646 (2004).
21. Colvin, V. L., Schlamp, M. C., Alivisatos, A. P. Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer. Nature 370, 354–357 (1994).
22. Dabbousi, B. O., Bawendi, M. G., Onitsuka, O. & Rubner, M. F. Electroluminescence from CdSe quantum-dot/polymer composites. Appl. Phys. Lett. 66, 1316–1318 (1995).
23. Mattoussi, H. et al. Electroluminescence from heterostructures of poly(phenylene vinylene) and inorganic CdSe nanocrystals. J. Appl. Phys. 83, 7965–7974 (1998).
24. Schlamp, M. C., Peng, X. & Alivisatos, A. P. Improved efficiencies in light emitting diodes made with CdSe(CdS) core/shell type nanocrystals and a semiconducting polymer. J. Appl. Phys. 82, 5837–5842 (1997).
25. Anikeeva, P. O., Halpert, J. E., Bawendi, M. G. & Bulović, V. Quantum dot light-emitting devices with electroluminescence tunable over the entire visible spectrum. Nano Lett. 9, 2532–2536 (2009).
26. Steckel, J. S. et al. Color-saturated green-emitting QD-LEDs. Angew. Chem. 45, 5796–5799 (2006).
27. Anikeeva, P. O., Madigan, C. F., Halpert, J. E., Bawendi, M. G. & Bulović, V. Electronic and excitonic processes in light-emitting devices based on organic materials and colloidal quantum dots. Phys. Rev. B 78, 085434 (2008).
28. Mueller, A. H. et al. Multicolor light-emitting diodes based on semiconductor nanocrystals encapsulated in GaN charge injection layers. Nano Lett. 5, 1039–1044 (2005).
29. Caruge, J. M., Halpert, J. E., Wood, V., Bulović, V. & Bawendi, M. G. Colloidal quantum-dot light-emitting diodes with metal-oxide charge transport layers. Nature Photon. 2, 247–250 (2008).
30. Wenyu Ji, Shihao Liu, Han Zhang, Rong Wang, Wenfa Xie, and Hanzhuang Zhang Ultrasonic Spray Processed, Highly Efficient All-Inorganic Quantum Dot Light-Emitting Diodes ACS Photonics 4, 1271−1278 (2017)
31. Caruge, J.-M., Halpert, J. E., Bulović, V. & Bawendi, M. G. NiO as an inorganic hole-transporting layer in quantum-dot light-emitting devices. Nano Lett. 6, 2991–2994 (2006).
32. Stouwdam, J. W. & Janssen, R. A. J. Red, green, and blue quantum dot LEDs with solution processable ZnO nanocrystal electron injection layers. J. Mater. Chem. 18, 1889–1894 (2008).
33. Caruge, J.-M., Halpert, J. E., Bulović, V. & Bawendi, M. G. NiO as an inorganic hole-transporting layer in quantum-dot light-emitting devices. Nano Lett. 6, 2991–2994 (2006).
34. Qian, L., Zheng, Y., Xue, J. & Holloway, P. H. Stable and efficient quantumdot light-emitting diodes based on solution-processed multilayer structures. Nature Photon. 5, 543–548 (2011).
35. Kim, L. et al. Contact printing of quantum dot light-emitting devices. Nano Lett. 8, 4513–4517 (2008).
36. Kim, T.-H. et al. Full-colour quantum dot displays fabricated by transfer printing. Nature Photon. 5, 176–182 (2011).
37. Brus, L. E. Electron-Electron and Electron-Hole Interactions in Small Semiconductor Crystallites-the Size Dependence of the Lowest Excited Electronic State. J. Chem. Phys 80, 4403−4409 (1984)
38. Masumoto, Y.; Sonobe, K. Size-Dependent Energy Levels of CdTe Quantum Dots. Phys. Rev. B: Condens. Matter Mater. Phys. 56, 9734−9737 (1997)
39. Colvin, V. L.; Schlamp, M. C.; Alivisatos, A. P. Light-EmittingDiodes Made from Cadmium Selenide Nanocrystals and a Semiconducting Polymer. Nature 370, 354−357 (1994)
40. Zhang, H.; Li, H. R.; Sun, X. W.; Chen, S. M. Inverted QuantumDot Light-Emitting Diodes Fabricated by All-Solution Processing. ACS Appl. Mater. Interfaces 8, 5493−5498 (2016)
41. Talapin, D. V.; Lee, J.; Kovalenko, M. V.; Shevchenko, E. V. Prospects of Colloidal Nanocrystals for Electronic and Optoelectronic Applications. Chem. Rev. 110, 389−458 (2010)
42. Bae, W. K.; Kwak, J.; Park, J. W.; Char, K.; Lee, C.; Lee, S. Highly Efficient Green-Light-Emitting Diodes Based on CdSe@ZnS Quan tum Dots with a Chemical-Composition Gradient. Adv. Mater. 21, 1690−1694 (2009)
43. Sun, Q.; Wang, Y. A.; Li, L. S.; Wang, D.; Zhu, T.; Xu, J.; Yang, C.; Li, Y. Bright, Multicoloured Light-emitting Diodes Based on Quantum Dots. Nat. Photonics 1, 717−722 (2007)
44. Coe, S.; Woo, W. K.; Bawendi, M. G.; Bulović, V. Electroluminescence from Single Monolayers of Nanocrystals in Molecular Organic Devices. Nature 420, 800−803 (2002)
45. Kwak, J. H.; Bae, W. K.; Lee, D. G.; Park, I.; Lim, J. H.; Park, M. J.; Cho, H. D.; Woo, H. J.; Yoon, D. Y.; Char, K. H.; Lee, S. H.; Lee, C. H. Bright and Efficient Full-Color Colloidal Quantum Dot LightEmitting Diodes Using an Inverted Device Structure. Nano Lett. 12, 2362−2366 (2012)
46. Mashford, B. S.; Stevenson, M.; Popovic, Z.; Hamilton, C.; Zhou, Z.; Breen, C.; Steckel, J.; Bulović, V.; Bawendi, M. G.; CoeSullivan, S.; Kazlas, P. T. High-Efficiency Quantum-Dot LightEmitting Devices with Enhanced Charge Injection. Nat. Photonics 7, 407−412 (2013)
47. Dai, X. L.; Zhang, Z. X.; Jin, Y. Z.; Niu, Y.; Cao, H. J.; Liang, X. Y.; Chen, L. W.; Wang, J. P.; Peng, X. G. Solution-Processed, HighPerformance Light-Emitting Diodes Based on Quantum Dots. Nature 515, 96−100 (2014)
48. Yang, Y. X.; Zheng, Y.; Cao, W. R.; Titov, A.; Hyvonen, J.; Manders, J. R.; Xue, J. G.; Holloway, P. H.; Qian, L. High-Efficiency Light-Emitting Devices Based on Quantum Dots with Tailored Nanostructures. Nat. Photonics 9, 259−266 (2015)
49. Caruge, J. M.; Halpert, J. E.; Bulović, V.; Bawendi, M. G. NiO as an Inorganic Hole-Transporting Layer in Quantum-Dot LightEmitting Devices. Nano Lett. 6, 2991−2994 (2006,)
50. Caruge, J. M.; Halpert, J. E.; Wood, V.; Bulović, V.; Bawendi, M. G. Colloidal Quantum-Dot Light-Emitting Diodes with Metal-Oxide Charge Transport Layers. Nat. Photonics 2, 247−250 (2008,)
51. Wood, V.; Panzer, M. J.; Halpert, J. E.; Caruge, J.-M.; Bawendi, M. G.; Bulović, V. Selection of Metal Oxide Charge Transport Layers for Colloidal Quantum Dot LEDs. ACS Nano 3, 3581−3586 (2009)
52. Wood, V.; Panzer, M. J.; Caruge, J.-M.; Halpert, J. E.; Bawendi, M. G.; Bulović, V. Air-Stable Operation of Transparent, Colloidal Quantum Dot Based LEDs with a Unipolar Device Architecture. Nano Lett. 10, 24 −29 (2010)
53. Mashford, B. S.; Nguyen, T.-L.; Wilson, G. J.; Mulvaney, P. All Inorganic Quantum-Dot Light-Emitting Devices Formed via Low Cost, Wet-Chemical Processing. J. Mater. Chem. 20, 167−172 (2010)
54. L. Y. Tanga, X. L. Zhanga, H. T. Dai, J. L. Zhaoa, S. G. Wanga, X. W. Sun. NiO as Hole Transport Layers for All-inorganic Quantum Dot LEDs Proc. of SPIE Vol. 8641 86410H-1
55. Chung, W.; Jung, H.; Lee, C. H.; Park, S. H.; Kim, J.; Kim, S. H. Synthesis and Application of Non-toxic ZnCuInS2/ZnS Nanocrystals for White LED by Hybridization with Conjugated Polymer. J. Electrochem. Soc. 158, 1218– 1220 (2011)
56. Chung,W.; Jung,H.; Lee,C.H.; Kim,S.H. Fabrication of High Color Rendering Index White LED Using Cd-Free Wavelength Tunable Zn Doped CuInS2 Nanocrystals. Opt. Express 20, 25071–25076 (2012)
57. Yin Zhang, Hui Gao, Jingjing Niu and Bitao LiuFacile synthesis and photoluminescence of graphene oxide quantum dots and their reduction products. New J. Chem. 38, 4970– 4974 (2014)
58. Jingbi You, Lei Meng, Tze-Bin Song, Tzung-Fang Guo, Yang (Michael) Yang, Wei-Hsuan Chang, Ziruo Hong, Huajun Chen, Huanping Zhou, Qi Chen, Yongsheng Liu, Nicholas De Marco and Yang Yang. Improved air stability of perovskite solar cells via solution-processed metal oxide transport layers. Nature Nanotechnology 11, 75–81 (2016)
59. Jesse R. Manders, Sai-Wing Tsang, Michael J. Hartel, Tzung-Han Lai, Song Chen, Chad M. Amb, John R. Reynolds, and Franky So. Solution-Processed Nickel Oxide Hole Transport Layers in High Efficiency Polymer Photovoltaic Cells.Adv. Funct. Mater. 23, 2993–3001 (2013)
60. Lei Qian, Ying Zheng, Kaushik R. Choudhury, Debasis Bera, Franky So, Jiangeng Xue, Paul H. Holloway Electroluminescence from light-emitting polymer/ZnO nanoparticle heterojunctions at sub-bandgap voltages Nano Today 5, 384—389 (2010)
61. Xingliang Dai, Zhenxing Zhang, Yizheng Jin, Yuan Niu, Hujia Cao, Xiaoyong Liang, Liwei Chen, Jianpu Wang & Xiaogang Peng Solution-processed, high-performance light-emitting diodes based on quantum dots. Nature 515, 96–99 (2014)
62. S.Y. Park, C.H. Lee, W.J. Song, C.Seoul. Enhanced electron injection in organic light-emitting devices using Al/ LiF electrodes. Current Applied Physics 1, 116–120 (2001)
63. Lei Qian, Ying Zheng, Jiangeng Xue and Paul H. Holloway Stable and efficient quantum-dot light-emitting diodes based on solution-processed multilayer structures. Nature Photonics 5, 543–548 (2011)
64. Hong Hee Kim, Soohyung Park, Yeonjin Yi, Dong Ick Son, Cheolmin Park, Do Kyung Hwang & Won Kook Choi. Inverted Quantum Dot Light Emitting Diodes using Polyethylenimine ethoxylated modified ZnO. Scientific Reports 5, Article number: 8968 (2015)
65. Huu Tuan Nguyen, Nang Dinh Nguyen and Soonil Lee. Application of solution-processed metal oxide layers as charge transport layers for CdSe/ZnSquantum-dot LEDs. Nanotechnology 24 (2013)
66. M. Caruge, J. E. Halpert, V. Wood, V. Bulovi & M. G. BawendiColloidal quantum-dot light-emitting diodes with metal-oxide charge transport layers J.Nature Photonics 2, 247 - 250 (2008)
67. Pegah Amini, Mahboubeh Dolatyari, Ali Rostami, Ghasem Rostami, Sanjay Mathur, and Pouneh Torabi High-Performance Solution Processed Inorganic Quantum Dot LEDs. IEEE Transactions on Nanotechnology 14, 911 - 917 (2015)
68. Wenyu Ji, Shihao Liu, Han Zhang, Rong Wang, Wenfa Xie, and Hanzhuang Zhang. Ultrasonic Spray Processed, Highly Efficient All-Inorganic Quantum Dot Light-Emitting Diodes. ACS Photonics 4, 1271−1278 (2017)
69. K. X. Steirer,R. E. Richards, A. K. Sigdel, A. Garcia, P. F. Ndione, S. Hammond,c D. Baker, E. L. Ratcliff, C. Curtis, T. Furtak, D. S. Ginley, D. C. Olson, N. R.Armstronga and J. J. Berry. Nickel oxide interlayer films from nickel formate–ethylenediamine precursor: influence of annealing on thin film properties and photovoltaic device performance. J. Mater. Chem. A 3, 10949 –10958 (2015)
70. Jesse R. Manders, Sai-Wing Tsang, Michael J. Hartel, Tzung-Han Lai,Song Chen, Chad M. Amb, John R. Reynolds, and Franky So. Solution-Processed Nickel Oxide Hole Transport Layers in High Efficiency Polymer Photovoltaic Cells. Adv. Funct. Mater. 23, 2993–3001 (2013)
71. K.K. Purushothaman, G. Muralidharan. The effect of annealing temperature on the electrochromic properties of nanostructured NiO films. Solar Energy Materials & Solar Cells 93, 1195–120 (2009)
72. Shuyi Liu, Rui Liu, Ying Chen, Szuheng Ho, Jong H. Kim, and Franky So. Nickel Oxide Hole Injection/Transport Layers for Efficient Solution Processed Organic Light-Emitting Diodes. Chem. Mater. 26, 4528−4534 (2014)
73. Xianwei Chu, Jiyan Leng, Jia Liu, Zhifeng Shi, Wancheng Li, Shiwei Zhuang, Hang Yang, Guotong Du, Jingzhi Yin. Effect of annealing conditions on the structural, electrical and optical properties of Li-doped NiO thin films. J Mater Sci: Mater Electron 27, 6408–6412 (2016)
74. Vikas Patil, Shailesh Pawar, Manik Chougule, Prasad Godse, Ratnakar Sakhare, Shashwati Sen, Pradeep Joshi. Effect of Annealing on Structural, Morphological, Electrical and Optical Studies of Nickel Oxide Thin Films. Journal of Surface Engineered Materials and Advanced Technology. 1, 35-41 (2011)
75. R. Noonuruk, N. Wongpisutpaisana, P. Mukdacharoenchaia, W. Techitdheerac and W. Pecharapa. Ozone-Induced Optical Density Change of NiO Thin Films and Their Applicability as Neutral Optical Density Filter. Procedia Engineering 8, 212–216 (2011)
76. A. K. Geim, Graphene: Status and Prospects. Science 324, 1530 (2009)
77. Y. Zhu, S. Murali, W. Cai, X. Li, J. W. Suk, J. R. Potts, R. S. Ruoff, Graphene and Graphene Oxide: Synthesis, Properties, and Applications. Adv. Mater. 22, 3906 (2010)
78. Jae Hwan Jung, Doo Sung Cheon Dr., Fei Liu, Kang Bum Lee, Tae Seok Seo Prof. A Graphene Oxide Based Immuno-biosensor for Pathogen Detection. Angew. Chem. Int. Ed. 49, 5708 –5711 (2010)
79. Kian Ping Loh, Qiaoliang Bao, Goki Eda & Manish Chhowalla. Graphene oxide as a chemically tunable platform for optical applications. Nature Chemistry 2, 1015–1024 (2010)
80. T. Gokus, R. R. Nair, A. Bonetti, M. Böhmler, A. Lombardo, K. S. Novoselov, A. K. Geim, A. C. Ferrari and A. Hartschuh. Making Graphene Luminescent by Oxygen Plasma Treatment. ACS Nano. 3, 3963–3968 (2009)
81. Fei Liu.Jong Young Choi.Tae Seok Seo. Graphene oxide arrays for detecting specific DNA hybridization by fluorescence resonance energy transfer. Biosensors and Bioelectronics 25, 2361-2365 (2010)
82. Z. Luo, P. M. Vora, E. J. Mele, A. T. C. Johnson, J. M. Kikkawa. Photoluminescence and Band Gap Modulation in Graphene Oxide. Appl. Phys. Lett. 94, 111909 (2009)
83. Goki Eda, Yun-Yue Lin, Cecilia Mattevi, Hisato Yamaguchi, Hsin-An Chen, I-Sheng Chen, Chun-Wei Chen, Manish Chhowalla. Blue Photoluminescence from Chemically Derived Graphene Oxide. Advanced Material 22, 505–509 (2010)
84. Phaedon Avouris. Graphene: Electronic and Photonic Properties and Devices. Nano Lett. 10, 4285–4294 (2010)
85. L.A.Ponomarenko, F.Schedin, M.I.Katsnelson, R.Yang, E.W.Hill, K.S.Novoselov, A.K.Geim. Chaotic Dirac Billiard in Graphene Quantum Dots. Science 320, 356-358 (2008)
86. Young-Woo Son, Marvin L. Cohen, and Steven G. Louie. Erratum: Energy Gaps in Graphene Nanoribbons. Phys. Rev. Lett. 97, 216803 (2006)
87. Xiaolin Li, Xinran Wang, Li Zhang, Sangwon Lee, Hongjie DaiChemically Derived, Ultrasmooth Graphene Nanoribbon Semiconductors. Science 29, 1229-1232 (2008)
88. Te-FuYeh, Chiao-YiTeng, Shean-JenChen, andHsisheng Teng. Nitrogen-Doped Graphene Oxide Quantum Dots as Photocatalysts for Overall Water-Splitting under Visible Light Illumination. Adv. Mater. 26, 3297–3303 (2014)
89. Te-Fu Yeh, Shean-Jen Chen, Hsisheng Teng. Synergistic effect of oxygen and nitrogen functionalities for graphene-based quantum dots used in photocatalytic H2 production from water decomposition. Nano Energy 12, 476–485 (2015)