State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China.
Biosens Bioelectron. 2014 Aug 15;58:219-25. doi: 10.1016/j.bios.2014.02.061. Epub 2014 Mar 6.
Heteroatom doping can drastically alter the electronic characteristics of graphene quantum dots (GQDs), thus resulting in unusual properties and related applications. Herein, we develop a simple and low-cost synthetic strategy to prepare nitrogen-doped GQDs (N-GQDs) through hydrothermal treatment of GQDs with hydrazine. The obtained N-GQDs with oxygen-rich functional groups exhibit a strong blue emission with 23.3% quantum yield (QY). Compared to GQDs, the N-GQDs exhibit enhanced fluorescence with blue-shifted energy. Due to the selective coordination to Fe(3+), the N-GQDs can be used as a green and facile sensing platform for label-free sensitive and selective detection of Fe (III) ions in aqueous solution and real water samples. The N-GQDs fluorescence probe shows a sensitive response to Fe(3+) in a wide concentration range of 1-1945μM with a detection limit of 90nM (s/N=3). Interestingly, it is also found that both dynamic and static quenching processes occur for the detection of Fe(3+) by N-GQDs, while the quenching effect of Fe(3+) on the fluorescence of GQDs is achieved by affecting the surface states of GQDs.
杂原子掺杂可以显著改变石墨烯量子点（GQDs）的电子特性，从而产生异常的性质和相关应用。在这里，我们开发了一种简单且低成本的合成策略，通过水热处理 GQDs 与水合肼来制备氮掺杂的 GQDs（N-GQDs）。得到的具有富氧官能团的 N-GQDs 具有 23.3%的量子产率（QY），呈现出强烈的蓝色发射。与 GQDs 相比，N-GQDs 具有能量蓝移增强的荧光。由于对 Fe(3+)的选择性配位，N-GQDs 可以用作一种绿色简便的传感平台，用于在水溶液和实际水样中对 Fe(III)离子进行无标记、敏感和选择性检测。N-GQDs 荧光探针对 Fe(3+)在 1-1945μM 的宽浓度范围内表现出敏感的响应，检测限为 90nM（S/N=3）。有趣的是，还发现 N-GQDs 对 Fe(3+)的检测既存在动态猝灭过程，也存在静态猝灭过程，而 Fe(3+)对 GQDs 荧光的猝灭效应是通过影响 GQDs 的表面状态来实现的。
