Rapid “turn-on” detection of atrazine using highly luminescent N-doped carbon quantum dot

Mohapatra, Sasmita; Bera, Mihir K.; Das, Rahul K.

doi:10.1016/j.snb.2018.02.155

Cited by 92 publications

(36 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In XPS, it is known that the appearance of peaks around 286, 400, and 532 eV corresponds to C 1s, N 1s, and O 1s, respectively. 46 After deconvolution, the C 1s XPS spectrum of CDs consisted of three peaks corresponding to the sp 2 -hybridized carbon atom C=C/C–C at 284.7 eV, C–OH at 286.3 eV, and O=C—O— of the carboxylic group at 288.57 eV. After functionalization, new peaks were observed confirming the formation of an amide linkage between the carboxylic group of CDs and NH of the PPQ molecule.…”

Section: Results and Discussionmentioning

confidence: 97%

Functionalized Chitosan–Carbon Dots: A Fluorescent Probe for Detecting Trace Amount of Water in Organic Solvents

et al. 2019

View full text Add to dashboard Cite

A novel nanoprobe was designed and synthesized by functionalizing chitosan–carbon dots (CDs) with a modified bipyridine-based heterocyclic molecule, 4-(pyridine-2-yl)-3 H -pyrrolo[2,3- c ]quinoline (PPQ), to detect trace amount of water via fluorescence methods. The functionalized CDs (PPQ-CDs) were thoroughly characterized using dynamic light scattering, UV–vis, X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and NMR techniques. The modified fluorescence intensity of PPQ-CDs was found to be an excellent indicator for water in organic solvents. The PPQ-CDs showed very weak fluorescence intensity in organic solvents due to a possible photoinduced electron transfer (PET) process between PPQ pyrrole nitrogen and acceptor groups of CDs. However, sequential addition of trace amount of water led to continuous enhancement in the fluorescence intensity for the PPQ-CD nanocomposites. The mechanism was proposed to follow suppression of the PET process due to the formation of “free-ions” by the proton transfer from the CD carboxyl group to pyrrole nitrogen through water bridging. The limit of water detection was determined to be 0.023% (v/v) in DMSO.

show abstract

Section: Results and Discussionmentioning

confidence: 97%

Functionalized Chitosan–Carbon Dots: A Fluorescent Probe for Detecting Trace Amount of Water in Organic Solvents

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Further addition of Au 3+ quenched the fluorescence of the C dots, which allowed detection of Au 3+ with LOD of 63.1 × 10 −9 m . Through analyte induced enhancement of fluorescence, nitrogen‐doped C dots with QY of 28% prepared from orthophenylene diamine through a hydrothermal method were used to determine the concentration of herbicide atrazine …”

Section: Sensing and Imaging Applicationsmentioning

confidence: 99%

Recent Advances and Sensing Applications of Carbon Dots

2019

View full text Add to dashboard Cite

Carbon dots (C dots) with biocompatibility, brightness, stability against photoirradiation and salt, and ease in preparation have become important materials for sensing and imaging. They can be prepared from natural materials and small organic molecules through hydrothermal, microwave‐assistant, and electrochemical methods, with advantages of simplicity and low cost. To enhance the quantum yields of C dots in the red and near‐infrared regions, doping of C dots with heteroatoms such as nitrogen and sulfur has been suggested. C dots both with and without being functionalized recognition elements such as antibodies and aptamers are selective and sensitive for sensing of analytes, including metal ions (e.g., Fe3+, Hg2+, Cu2+), small molecules (e.g., H2O2, cysteine, glutathione), and biopolymers like proteins, as well as for in vitro and in vivo imaging. Depending on the size, charge, and surface ligands of C dots used to label cells, fluorescence images of different organelles are shown. Multicolor images of bacteria, mammalian cells, and plant tissues incubated with C dots are realized when excited at different wavelengths. In this review, many excellent sensing and imaging examples of C dots are presented to highlight their features and to show their challenges for analytical applications.

show abstract

“…In the absence of urea at elevated temperature, p -PDA immediately forms dimers and trimers. The formation of rigid polymers containing phenazine units occurred 4 after polymerization of these oligomers, and thereafter N-GQDs (N-GQD1) are formed via the carbonization process. Under hydrothermal condition, the polymerization is mostly due to the formation of radical cations and radical coupling, 4 leading to the synthesis of N-GQDs containing several amino/hydroxyl functional groups on their surfaces.…”

Section: Resultsmentioning

confidence: 99%

“…The fascinating optical properties of graphene quantum dots (GQDs) have led to new advancements for its photonic applications. GQDs have a number of distinct merits, such as low toxicity, high photostability, and easy synthesis, 1,2 which make them attractive for applications in bioimaging, 3 sensors, 4 energy storage, 5 and optoelectronic devices. 6−10 The optical properties of GQDs are still regarded as an imperative research topic, to reveal the exact origin of their luminescence and to optimize it for light-emitting applications.…”

Section: Introductionmentioning

confidence: 99%

Colloidal N-Doped Graphene Quantum Dots with Tailored Luminescent Downshifting and Detection of UVA Radiation with Enhanced Responsivity

et al. 2018

View full text Add to dashboard Cite

Luminescent downshifting (LDS) materials are in great demand for their applications in light conversion devices. In this work, by an ingenious chemical approach of in situ doping, N-doped graphene quantum dots (N-GQDs) have been synthesized with tailored green photoluminescence (PL) under ultraviolet (UV) light excitation. The incorporation of N atoms in the form of pyridinic and graphitic C–N bonding into the sp 2 -hybridized graphitic framework of N-GQDs has led to tailored LDS via PL emissions. The LDS property of synthesized N-GQDs has been advantageously utilized to demonstrate enhanced responsivity ( R ) of a low-cost commercially available photoconductive cell (PC) for detection of UVA radiation through an indigenous technique. The linear optical responses of samples are optimized by varying the concentration and the dispersing medium. Also the N-GQDs are shown to be photostable in poly(vinyl alcohol) (PVA) hydrogel. A 60% enhancement in photocurrent of the PC-based photodetector under UV radiation has been obtained here by using N-GQDs/PVA as LDS material. Thus, detection of UVA radiation with a high specific detectivity ( D *) of 9 × 10 13 Jones and responsivity ( R ) of 3 A W –1 has been demonstrated, which might open the opportunity of using this material in future energy conversion devices.

show abstract

Rapid “turn-on” detection of atrazine using highly luminescent N-doped carbon quantum dot

Cited by 92 publications

References 46 publications

Functionalized Chitosan–Carbon Dots: A Fluorescent Probe for Detecting Trace Amount of Water in Organic Solvents

Functionalized Chitosan–Carbon Dots: A Fluorescent Probe for Detecting Trace Amount of Water in Organic Solvents

Recent Advances and Sensing Applications of Carbon Dots

Colloidal N-Doped Graphene Quantum Dots with Tailored Luminescent Downshifting and Detection of UVA Radiation with Enhanced Responsivity

Contact Info

Product

Resources

About