4-nitrophenol optical sensing with N doped oxidized carbon dots

N. K.R. Bogireddy, R. Cruz Silva, Miguel A. Valenzuela, Vivechana Agarwal

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


© 2019 Elsevier B.V. In this work, we report a facile strategy for 4-nitrophenol (4-NP) sensing using highly luminescent nitrogen-doped oxidized carbon dots. The quenching of fluorescence (turn OFF), with the addition of trace amounts of organic pollutant (4-NP) in NOCDs, has been attributed to the complete reduction of nitrogen-doped oxidized carbon dots (NOCDs) to reduced nitrogen-doped oxidized carbon dots (rNOCDs) and its formation was confirmed by infrared, X-ray diffraction and X-ray photoelectron spectroscopy measurements. The chemical changes in oxygen-containing functional groups of NOCDs, in the presence of 4-NP, are elucidated and corresponding characterization through XPS reveals the changes in the peak intensities of C[sbnd]C (284.5 eV) and O[sbnd]C[dbnd]O (288.6 eV), indicating a decrement in hydroxyl groups that hinder its complete reduction to NOCDs. The sensitivity of NOCDs towards 4-NP has been tested in spiked tap water in the concentration range 2 μM to 2 mM with the minimum detection limit of 2 μM (linear detection range from 2 to 100 μM with regression coefficient R2 =0.99). The proposed simple sensing platform can be used to reduce NOCDs and simultaneously sense low concentrations of 4-NP. Finally, an effective treatment to improve the reduction of nitrogen-doped graphene oxide is proposed.
Original languageAmerican English
JournalJournal of Hazardous Materials
StatePublished - 15 Mar 2020


Dive into the research topics of '4-nitrophenol optical sensing with N doped oxidized carbon dots'. Together they form a unique fingerprint.

Cite this