Solvent-free Synthesis of Flowable Carbon Clusters with Customizable Size and Tunable Optical Performance  

作　　者：Denian Li Qi Li Xuan Hu Jing Huang Hairong Li Lijie Dong HaJan Xie Chuanxi Xiong 

机构地区：[1]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materiah' Science and Engineering, Wuhan University of Technology, Wuhan, Hubei 430070, China [2]School of Materials Science and Engineering, Wuhan Textile University, Wuhan, Hubei 430073, China

出　　处：《Chinese Journal of Chemistry》2013年第12期1513-1518,共6页中国化学（英文版）

基　　金：The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China，the 973 Program

摘　　要：We propose a rapid and solvent-flee route for synthesizing luminous carbon clusters by controlling carbonization of polyethylene glycol （PEG）. This approach does not involve solvents yet uses the precursor itself as suspend- ing medium, thus features mild and green chemistry, and also enables the formation of uniform-sized carbon clus- ters, of which the diameter can be easily tuned from 0.7 to 3.5 nm via control of reaction time. In term of the di- mension, the resultants are denoted as sub-nano carbon clusters （SNCs） and carbon dots （CDs）, respectively. Bene- fiting from surface anchored PEG segments, both of the two show favorable flowability at room temperature and excellent solubility in aqueous and organic solvents. Comparison of their optical performances and structures re- veals that they share the same chromophores. Particularly, the SNCs demonstrate robust photo- and pH-stable pho- toluminescence and can be directly applied to cell-imaging regarding to its prominent biocompatibility. Moreover, its quantum yield （5.5%）, which is approximately 3 times higher than that of CDs （1.5%）, can be dramatically en- hanced to 18.8% by facile chemical reduction. We anticipate that these PEG derivatives marked with easy synthesis, controllable optical performances and excellent physical properties will be highly appealing in future applications.We propose a rapid and solvent-flee route for synthesizing luminous carbon clusters by controlling carbonization of polyethylene glycol （PEG）. This approach does not involve solvents yet uses the precursor itself as suspend- ing medium, thus features mild and green chemistry, and also enables the formation of uniform-sized carbon clus- ters, of which the diameter can be easily tuned from 0.7 to 3.5 nm via control of reaction time. In term of the di- mension, the resultants are denoted as sub-nano carbon clusters （SNCs） and carbon dots （CDs）, respectively. Bene- fiting from surface anchored PEG segments, both of the two show favorable flowability at room temperature and excellent solubility in aqueous and organic solvents. Comparison of their optical performances and structures re- veals that they share the same chromophores. Particularly, the SNCs demonstrate robust photo- and pH-stable pho- toluminescence and can be directly applied to cell-imaging regarding to its prominent biocompatibility. Moreover, its quantum yield （5.5%）, which is approximately 3 times higher than that of CDs （1.5%）, can be dramatically en- hanced to 18.8% by facile chemical reduction. We anticipate that these PEG derivatives marked with easy synthesis, controllable optical performances and excellent physical properties will be highly appealing in future applications.

关 键 词：solvent-free synthesis carbon clusters customizable size FLUORESCENCE 

分 类 号：O484.41[理学—固体物理] TQ223.24[理学—物理]