本文以柠檬酸（CA）为碳源、三聚氰胺（MEM）为氮源、植酸（PA）为羟基源,并引入多孔二氧化硅（Nano-SiO2）作为阻隔剂,通过微波法制备了一种具有激基缔合物特征的荧光碳点（CDs）。研究表明,当反应物CA/MEM/PA/Nano-SiO2的摩尔比为20:1:10:1000时,合成的DuY8-CDs在水溶液和固态下均具有最高的荧光量子产率。实验发现,DuY8-CDs在低浓度水溶液中发射448 nm的蓝色荧光;随着其在水溶液中浓度增大,短波长处的蓝色荧光峰逐渐减弱,长波处的黄色荧光峰逐渐增强,表现出典型的激基缔合物发光特征。与DuY8-CDs在低浓度水溶液中的荧光量子产率（39.31%）相比,其在固态下的荧光量子产率提升至50.31%。基于DuY8-CDs固态下的有效黄光发射,以DuY8-CDs为荧光粉制备了CIE坐标为（0.32,0.41）、发光亮度达到26350 cd m-2的白光LED器件。
Dong
,
Linlin
,
Zhao
,
Shijie
,
Shi
,
Mingkai
,
Xie
,
Tianyou
,
Jia
,
Yixin
,
Zhou
,
Jinpeng
,
Miao
,
Yanqin
,
Guo
,
Kunpeng
. 具有激基缔合物特征的荧光碳点的制备及在白光LED中的应用[J]. 化学学报, 0
: 0
.
DOI: 10.6023/A25030078
From the view point of practical application, the urgent problem to be solved in the field of carbon dots is how to effectively overcome the aggregation-induced fluorescence quenching effect in solid state to avoid a significant decrease in photoluminescence quantum yield (PLQY). Studies have shown that excimers formed by π-π stacking or charge transfer between organic molecules can reduce non-radiative transitions, and thus increasing PLQY. Motivated by this, we prepared carbon dots with excimer characteristic by using citric acid (CA) as carbon source, melamine (MEM) as nitrogen source, phytic acid (PA) as hydroxyl source and nano-silica (Nano-SiO2) as barrier agent with a microwave synthesis. Studies found that by optimizing the molar ratio of the four reactants CA/MEM/PA/Nano-SiO2 to 20:1:10:1000, the as-prepared DuY8-CDs showed the best performance. The detailed synthetic procedure is as following: CA (1.38 g, 7.2 mmol), MEM (0.04 g, 0.36 mmol) and PA (2.38 g, 3.6 mmol) were added to 20 mL formamide in a beaker, and ultrasonically stirred until a transparent solution was formed. Subsequently, the solution was heated under a 700 W microwave for 5 min to obtain a black gel. The obtained black colloidal substance was ultrasonically dispersed in 40 mL anhydrous ethanol, added with Nano-SiO2 (21.62 g, 360 mmol) and stirred for 24 h. Then the mixture was filtered and the filter was placed in a blast drying oven at 120 ℃ for 20 min. The obtained powder was ground to obtain the fluorescent carbon dot DuY8-CDs. It was found that low concentration DuY8-CDs aqueous solution emitting blue fluorescence at 448 nm. By increasing its concentration, the blue emission band in higher energy region was gradually weakened and the yellow emission band in lower energy region was gradually increased, which indicate the formation of excimer in high concentration solution. The DuY8-CDs exhibited photoluminescence quantum yield of 39.31% and 50.31% in aqueous solution and solid state, respectively. Based on its effective yellow emission in solid state, white LED devices based on DuY8-CDs were fabricated, which exhibited a CIE coordinate of (0.32, 0.41), and a maximum luminance of 26350 cd m-2 at 3.8 V work voltage. This work paves a new way for developing CDs with efficient emission in solid state.
[1] Qi L.; Liu S.; Ping J.; Yao X.; Chen L.; Yang D.; Liu Y.; Wang C.; Xiao Y.; Qi L.; Jiang Y.; Fang X. Biosensors 2024,14, 314.
[2] Wang Y. P.; Yuan P. X.; Zhang J. Y.; Wang B.; Yang L. P.; Wang L. L. Microchemical Journal 2025, 211, 113151.
[3] Zhu L.; Shen D.; Wang Q.; Luo K. H. ACS Appl. Mater. Interfaces 2021, 13, 56465.
[4] Li N.-H.;Zhang Q.-M.; Yang G.-Q.; Cheng Z.-W.; Duan X.-J.; Sun, L.-X., Wang W.; Li B. Chin. J. Lumin. 2024, 45, 2054 (in Chinese).
李乃辉; 张清梅; 杨国庆; 程泽伟; 杜秀娟; 孙凌翔; 王伟; 李冰发光学报 2024, 12, 2054.
[5] Wang X. H.; Zhang Y. M.; Li J. Z.; Liu G. J.; Gao M. Z.; Ren, S. H; Liu, B. X.; Zhang L. X.; Han, G. T.; Yu, J. Y.; Zhao, H. G.; Rosei, F. Small Methods 2022, 6, 2101470.
[6] Zhang Z.; Qu D.; An L.; Wang X.-Y.; Sun, Z.-C. Chin. J. Lumin. 2021, 42, 1125 (in Chinese).
张震; 曲丹; 安丽; 汪夏燕; 孙再成. 发光学报 2021, 42, 1125.
[7] Li Y.-N.; Liu Y.; Liu C.-Y.; Xiao J.-P. Journal of Materials Engineering 2023, 51, 14 (in Chinese).
李亚楠; 刘云; 刘春艳; 肖军平, 材料工程 2023, 51, 14.
[8] Jiang K.; Sun, S., Zhang L.; Lu Y.; Wu A. G.; Cai C. Z.; Lin H. W. Angew. Chem. Int.Ed. 2015, 54, 5360.
[9] Wei S. S.; Wang B.; Zhang H. Y.; Wang C. Z.; Cui S. F.; Yin X. Y.; Jiang C. Z.; Sun G. Y. Chemical Engineering Journal 2023, 466, 143103.
[10] Xu A.; Wang G.; Li Y.; Dong H.; Yang S.; He P.; Ding G. Small 2020, 48, 2004621.
[11] Wang H. L.; Ai L.; Song H. Q.; Song Z. Q.; Yong X.; Qu S. N.; Lu S. Y. Adv. Funct. Mater. 2023, 33, 2303756.
[12] Huang C.-Y.; Tian R.; Zhang D.; Duan T.-T.; Li A.-B.; Wang Q.; Rong M.-Z.; Wang, Z.-L. Chin. J. Lumin. 2024, 45, 1292 (in Chinese).
黄彩艳; 田蕊; 张朵; 段婷婷; 李爱波; 王琴; 戎梅竹; 汪正良. 发光学报 2024, 45, 1292.
[13] Wang J. L.; Li Q.; Zheng J. X.; Yang Y. Z.; Liu X. G.; Xu B. S.Acs Sustain. Chem. Eng. 2021, 9, 2224.
[14] Wang Z. B.;Jiang N, Z.; Liu, M. L.; Zhang, R. D.; Huang, F.; Chen. D. Q. Small 2021, 17, 2104551.
[15] Qu Y. F.; Bai X. W.; Li D.; Zhang X. Y.; Liang C.; Zheng W. T.; Qu S. N. Journal of Colloid and Interface Science, 2022, 613, 547.
[16] An Y. L.; Liu C.; Chen M.; Yin X. J.; Hou D. F.; Zheng Y. W.; Shi R.; He X. H.; Lin X.ACS Sustainable Chem.Eng. 2023, 11, 23.
[17] Zheng M. Y.; Jia H. R.; Zhao B.; Zhang C. Y.; Dang Q.; Ma H. Y.; Xu K. X.; Tan Z. A .Small 2023, 19, 2206715.
[18] Xu W. J.; Zeng F. H.; Han Q. R.; Peng Z. L. Coord. Chem. Rev. 2024, 498, 215469.
[19] Zhang H. Y.; Zhang M.; Zhuo H.; Yang H. Y.; Han B.; Zheng Y. H.; Wang H.; Lin H.; Tao S.-L.; Zheng C. J.; Zhang X. H. Chemical Science 2024, 36, 14651.
[20] Wang W.; Wang Y.; Yuan K.; Yang B.; Yang X.; Zou B.Laser Photonics Rev. 2025, 3, 2401173.
[21] Feng X.; Wang X.; Redshaw C.; Tang B. Z. Chem. Soc. Rev. 2023, 52, 6715.
[22] Sun C. X.; Li B. H.; Zhao M. Y.; Wang S. F.; Lei Z. H.; Lu L. F.; Zhang H. X.; Feng L. H.; Dou C. R.; Yin D. R.; Xu H. X.; Cheng Y. S.; Zhang F. J. Am. Chem. Soc. 2019, 141, 19221.
[23] Xie Z. Y.; Liu D.; Zhao Z. N.; Gao C.; Wang P.; Jiang C. X.; Liu X. F.; Zhang X. T.; Ren Z. J.; Yan S. K.; Hu W. P.; Dong H. L. Angew. Chem. Int.Ed. 2024, 63, e202319380.
[24] Shan X.; Chi W.; Jiang H.; Luo Z.; Qian C.; Wu H.; Zhao Y. Angew. Chem. Int. Ed. 2023, 4, e202215652.
[25] Fang M.; Yang J.; Li Z. Progress in Materials Science 2022, 125, 100914.
[26] Ozyurt D.; Shafqat S.; Pakkanen, T. T, Hocking, R. K.; Mouritz A.; Fox B. Carbon 2021, 175, 576.
[27] Chen M.; Du B.; Wang Q.; Zhang J.; Zhu X.; Lin Z.; Dong Y.; Fu F.; Yu T. Carbon 2021, 185, 442.
[28] Xiao D.; Jiang M.; Luo X.; Liu S.; Li J.; Chen Z.; Li S. ACS Sustainable Chem.Eng. 2021, 11, 4139.
[29] Wang J.; Sun X.; Pan W.; Wang J. Microchemical Journal 2022, 178, 107408.
[30] Xia C.; Zhu S.; Feng T.; Yang M.; Yang B. Advanced Science 2019, 23, 1901316.
[31] Dong X.-Y.; Niu X.-Q.; Zhang Z. Y.; Wei J. S.; Xiong H. M. ACS Appl. Mater. Interfaces 2020, 26, 29549.
[32] Kalytchuk S.; Poláková K.; Wang Y.; Froning J. P.; Cepe K.; Rogach A. L.; Zbořil R. ACS Nano 2017, 2, 1432.
[33] Wei B.; Dong F.; Yang W.; Luo C.; Dong Q.; Zhou Z.; Yang Z.; Sheng L. Journal of Advanced Research 2020, 23, 13.
