Details

Autor(en) / Beteiligte

• Shi, Bingfang
• Zhang, Liangliang
• Lan, Chuanqing
• Zhao, Jingjin
• Su, Yubin
• Zhao, Shulin

Titel

One-pot green synthesis of oxygen-rich nitrogen-doped graphene quantum dots and their potential application in pH-sensitive photoluminescence and detection of mercury(II) ions

Ist Teil von

• Talanta (Oxford), 2015-09, Vol.142, p.131-139

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2015

Quelle

MEDLINE

Beschreibungen/Notizen

• Nitrogen doping has been a powerful method to modulate the properties of carbon materials for various applications, and N-doped graphene quantum dots (GQDs) have gained remarkable interest because of their unique chemical, electronic, and optical properties. Herein, we introduce a facile one-pot solid-phase synthesis strategy for N-doped GQDs using citric acid (CA) as the carbon source and 3,4-dihydroxy-l-phenylalanine (l-DOPA) as the N source. The as-prepared N-GQDs with oxygen-rich functional groups are uniform with an average diameter of 12.5nm. Because of the introduction of nitrogen atoms, N-GQDs exhibit excitation-wavelength-independent fluorescence with the maximum emission at 445nm, and a high quantum yield of 18% is achieved at an excitation wavelength of 346nm. Furthermore, a highly efficient fluorosensor based on the as-prepared N-GQDs was developed for the detection of Hg2+ because of the effective quenching effect of metal ions via nonradiative electron transfer. This fluorosensor exhibits high sensitivity toward Hg2+ with a detection limit of 8.6nM. The selectivity experiments reveal that the fluorescent sensor is specific for Hg2+. Most importantly, the practical use of the sensor based on N-GQDs for Hg2+ detection was successfully demonstrated in river-water samples. [Display omitted] •Oxygen-rich nitrogen-doped graphene quantum dots were synthesized.•The oxygen-rich nitrogen-doped graphene quantum dots can be used for pH measurement.•High selective and sensitive method for Hg2+ detection was developed.