Carbon Nanodots-Catalyzed Chemiluminescence of Luminol: A Singlet Oxygen-Induced Mechanism

详细信息    查看全文

• 作者：Dong Mei Wang ; Ming Xuan Gao ; Peng Fei Gao ; Hui Yang ; Cheng Zhi Huang
• 刊名：Journal of Physical Chemistry C
• 出版年：2013
• 出版时间：September 19, 2013
• 年：2013
• 卷：117
• 期：37
• 页码：19219-19225
• 全文大小：344K
• 年卷期：v.117,no.37(September 19, 2013)
• ISSN：1932-7455

文摘

The catalyzed luminol chemiluminescence (CL) in a strongly alkaline environment has been rarely induced by singlet oxygen (¹O₂). This paper reports that cetyltrimethyl ammonium bromide passivated carbon nanodots (CTAB-CDs), prepared by the hydrothermal treatment of fullerene in the presence of CTAB, can be used as excellent catalysts to dramatically enhance the CL intensity of the luminol鈥揌₂O₂ system in NaOH medium owing to their unique surface property. More importantly, this CL enhancement takes place mainly through the intermediate of ¹O₂, which follows a different mechanism from traditional reports. The CL spectra, UV鈥搗is spectra, electron paramagnetic resonance (EPR) spectra, transmission electron microscopy (TEM) images before and after the CL reaction, and the effects of various free radical scavengers on the CL intensity were conducted to identify the possible ¹O₂-participating CL enhancement mechanism. It was demonstrated that the CL enhancement by CTAB-CDs originated from the processes of the catalysis of CDs on the electron-transfer and the breakdown of H₂O₂. Both processes produced a great amount of ¹O₂ on the surface of CTAB-CDs, and then the reaction of ¹O₂ with luminol resulted in an unstable endoperoxide, which could rapidly decompose into the excited state 3-aminophthalate anions (3-APA*), leading to the enhanced CL at 440 nm. The important features of this CDs-catalyzed CL will not only enrich traditional luminol CL mechanism in strongly alkaline conditions but also open up a new route to study this novel carbon nanomaterial, which may broaden the applications in a large variety of fields.