title: One-step microwave synthesis of N-doped hydroxyl-functionalized carbon dots with ultra-high fluorescence quantum yields.
abstract: A one-step microwave synthesis of N-doped hydroxyl-functionalized carbon dots (CDs) with ultra-high fluorescence quantum yields (QYs) of 99% is reported. These ultra-high QY CDs were synthesized using citric acid and amino compound-containing hydroxyls like ethanolamine and tris(hydroxylmethyl)aminomethane. Amino and carboxyl moieties can form amides through dehydration condensation reactions, and these amides act as bridges between carboxyl and hydroxyl groups, and modify hydroxyl groups on the surface of the CDs. The entire reaction can be carried out within 5 min. When the molar ratio of reactants is 1 : 1, the hydroxyl and graphitic nitrogen content is the highest, and the synergy leads to a high ratio between the radiative transition rate and nonradiative transition rate as well as a high QY. The developed pathway to N-doped hydroxyl-functionalized CDs can provide unambiguous and remarkable insights into the design of highly luminescent functionalized carbon dots, and expedite the applications of CDs.
authors: State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. liuxy@ciomp.ac.cn linj@ciomp.ac.cn and University of Chinese Academy of Sciences, Beijing, 100049, China.
authors: Yongqiang
authors: Y
authors: Zhang
authors: State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. liuxy@ciomp.ac.cn linj@ciomp.ac.cn.
authors: Xingyuan
authors: X
authors: Liu
authors: State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. liuxy@ciomp.ac.cn linj@ciomp.ac.cn.
authors: Yi
authors: Y
authors: Fan
authors: State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. liuxy@ciomp.ac.cn linj@ciomp.ac.cn.
authors: Xiaoyang
authors: X
authors: Guo
authors: State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China. ammszhoulei@aliyun.com.
authors: Lei
authors: L
authors: Zhou
authors: State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. liuxy@ciomp.ac.cn linj@ciomp.ac.cn.
authors: Ying
authors: Y
authors: Lv
authors: State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. liuxy@ciomp.ac.cn linj@ciomp.ac.cn.
authors: Jie
authors: J
authors: Lin