Surface-state controlled synthesis of hydrophobic and hydrophilic carbon dots  

作　　者：Chan Wang Yuan Fang Mi Zhang Huan Zhuo Qijun Song Han Zhu 

机构地区：[1]Key Laboratory of Synthetic and Biological Colloids,Ministry of Education,School of Chemical and Material Engineering,Jiangnan University,Wuxi 214122,China [2]Jiangsu Snow Leopard Household Chemical Co.,Ltd.,Wuxi 214400,China

出　　处：《Nano Research》2024年第5期4391-4399,共9页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.51973083,22376081);the Fundamental Research Funds for the Central Universities(No.JUSRP22027).

摘　　要：It is of great significance to synthesize carbon dots(CDs)with desirable hydrophilicity for the ever-growing application of CDs in different fields.In this study,the hydrophilic and hydrophobic CDs were facilely prepared by solvothermal treatment of o-dihydroxybenzene and urea in N,N-dimethylformamide(DMF).Optimization experiments revealed that the solvothermal temperature has a great impact on the surface states of the CDs.The hydrophobic CDs with a contact angle of 110.7°was obtained at 200℃.The structural and optical characterizations,along with theoretical calculations elucidated that the lipophilic nature of the CDs was resulting from the formation of polymer chains.The presence of extended conjugated sp^(2)-domains and amino groups contributed to the red emission of the CDs synthesized at low reaction temperatures(160-200℃).With the further increase of solvothermal temperature,the hydrophobic CDs were gradually transformed to the hydrophilic state accompanying the blue shift of the fluorescence of the CDs.The highly hydrophilic CDs with a contact angle of 25.9°were obtained at 240℃ due to the increased formation of hydrophilic functional groups on the surface of CDs.The red emissive CDs exhibited a sensitive color and fluorescence response to ethanol content while the fluorescence of the blue emissive CDs remained constant.By combining the two kinds of CDs,a dual-emission sensor was constructed,which was successfully applied for the evaluation of the alcoholic strength in commercial Baijiu commodities in both fluorometric and colorimetric modes.

关 键 词：carbon dots surface chemistry hydrophilicity and hydrophobicity solvothermal temperature alcoholic strength evaluation 

分 类 号：O62[理学—有机化学]