A new turn-off fluorescence probe based on graphene quantum dots for detection of Au(III) ion

Amjadi, Mohammad; Shokri, Roghayeh; Hallaj, Tooba

doi:10.1016/j.saa.2015.09.037

Cited by 40 publications

(11 citation statements)

References 52 publications

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“…The PL peaks are shifted from 413 to 466 nm and their intensities are decreased as excitation wavelengths exceeded from 340 to 400 nm. This excitation-dependent PL behavior was extensively reported in fluorescent carbon-based nanomaterials 25,26 and is caused by the electronic conjugate structures, free zigzag sites and the wide distributions of differently sized dots 26,27 .…”

Section: Resultsmentioning

confidence: 54%

Highly Luminescent Ternary Nanocomposite of Polyaniline, Silver Nanoparticles and Graphene Oxide Quantum Dots

Shokry

Khalil

Ibrahim

et al. 2019

Sci Rep

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Quantum dots (QDs) with photostability show a potential application in optical sensing and biological imaging. In this work, ternary nanocomposite (NC) of high fluorescent polyaniline (PANI)/2-acrylamido-2-methylpropanesulfonic acid (AMPSA) capped silver nanoparticles (NPs)/graphene oxide quantum dots (PANI/Ag (AMPSA)/GO QDs) have been synthesized by in situ chemical oxidative polymerization of aniline in the presence of Ag (AMPSA) NPs and GO QDs. Ag (AMPSA) NPs and GO QDs were prepared by AgNO3 chemical reduction and glucose carbonization methods, respectively. The prepared materials were characterized using UV-visible, Fourier transform infrared (FTIR), photoluminescence and Raman spectroscopies, X-Ray diffractometer (XRD) and high- resolution transmission electron microscopy (HRTEM). HRTEM micrographs confirmed the preparation of GO QDs with an average size of 15 nm and Ag (AMPSA) NPs with an average size of 20 nm. PANI/Ag (AMPSA)/GO QDs NC showed high and stable emission peak at 348 nm. This PANI/Ag (AMPSA)/GO QDs NC can emerge as a new class of fluorescence materials that could be suitable for practical sensing applications.

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Section: Resultsmentioning

confidence: 54%

Highly Luminescent Ternary Nanocomposite of Polyaniline, Silver Nanoparticles and Graphene Oxide Quantum Dots

Shokry

Khalil

Ibrahim

et al. 2019

Sci Rep

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“…It is proposed that the benzenoid rings are responsible for the fluorescence while at low pH the PANI is protonated and the conductive (quinoid rings) regions act as a fluorescence quencher 23 . Moreover, at low pH the aggregation of PANI/Ag (AMPSA)/GO QDs is manifested by the action of intramolecular hydrogen bond of the carboxylic acid moieties existed onto the surface of the PANI/Ag (AMPSA)/GO QDs 24 , 25 . On the other hand, PANI/Ag (AMPSA)/GO QDs is exhibited a new fluorescence band in the visible region (427 nm) at pH 2 as a result of the formation of ground state species by electron donor–acceptor interaction between emeraldine salt and GO QDs or charge transfer interaction within the PANI-GO QDs 26 .…”

Section: Resultsmentioning

confidence: 99%

Polyaniline/Ag nanoparticles/graphene oxide nanocomposite fluorescent sensor for recognition of chromium (VI) ions

Ebrahim

Shokry

Khalil

et al. 2020

Sci Rep

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Selective determination of toxic hexavalent chromium (Cr(VI)) is a stringent important due to its huge negative impact on the health and environment. Recently, the high sensitivity, rapidness, and cost-effectiveness of the fluorescent sensors for Cr(VI) have been developed. A fluorescent nanocomposite (NC) has been synthesized based on doped polyaniline (PANI), 2-acrylamido-2-methylpropanesulfonic acid (AMPSA) capped Ag nanoparticles (NPs) and graphene oxide (GO) quantum dots (QDs) via in situ reaction for highly selective sensing of Cr(VI) ions based on the luminescent quenching in the range from 0.01 to 7.5 mg/L. This NC showed an emission peak at 348 nm with a linear range from 0.01 to 0.05 mg/L and the low limit of detection (LOD) was 0.0065 mg/L (~ 6 µg/L). PANI/Ag (AMPSA) GO QDs NC displayed high selectivity for Cr(VI) over other common metal ions. Notably, the PANI/Ag (AMPSA) GO QDs NC can be used for distinguishing Cr(VI) and Cr(III) in solutions. The sensitive determination of Cr(VI) in real surface water samples was also confirmed and demonstrated recoveries in the range 95.3–99.2%. This NC will emerge as a new class of fluorescence materials that could be suitable for practical applications.

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“…Since then, PAR has been widely used as a chromogenic reagent for the detection of mainly metal ions. Besides PAR, other materials such as quantum dots (QDs) are also reported to have excellent properties for potential metal ion sensing [ 34 , 35 , 36 , 37 ]. QDs are made up from atoms of groups II–VI, III–V, or IV–VI elements in the periodic table.…”

Section: Introductionmentioning

confidence: 99%

X-ray Photoelectron Spectroscopy Analysis of Chitosan–Graphene Oxide-Based Composite Thin Films for Potential Optical Sensing Applications

et al. 2021

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In this study, X-ray photoelectron spectroscopy (XPS) was used to study chitosan–graphene oxide (chitosan–GO) incorporated with 4-(2-pyridylazo)resorcinol (PAR) and cadmium sulfide quantum dot (CdS QD) composite thin films for the potential optical sensing of cobalt ions (Co2+). From the XPS results, it was confirmed that carbon, oxygen, and nitrogen elements existed on the PAR–chitosan–GO thin film, while for CdS QD–chitosan–GO, the existence of carbon, oxygen, cadmium, nitrogen, and sulfur were confirmed. Further deconvolution of each element using the Gaussian–Lorentzian curve fitting program revealed the sub-peak component of each element and hence the corresponding functional group was identified. Next, investigation using surface plasmon resonance (SPR) optical sensor proved that both chitosan–GO-based thin films were able to detect Co2+ as low as 0.01 ppm for both composite thin films, while the PAR had the higher binding affinity. The interaction of the Co2+ with the thin films was characterized again using XPS to confirm the functional group involved during the reaction. The XPS results proved that primary amino in the PAR–chitosan–GO thin film contributed more important role for the reaction with Co2+, as in agreement with the SPR results.

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A new turn-off fluorescence probe based on graphene quantum dots for detection of Au(III) ion

Cited by 40 publications

References 52 publications

Highly Luminescent Ternary Nanocomposite of Polyaniline, Silver Nanoparticles and Graphene Oxide Quantum Dots

Highly Luminescent Ternary Nanocomposite of Polyaniline, Silver Nanoparticles and Graphene Oxide Quantum Dots

Polyaniline/Ag nanoparticles/graphene oxide nanocomposite fluorescent sensor for recognition of chromium (VI) ions

X-ray Photoelectron Spectroscopy Analysis of Chitosan–Graphene Oxide-Based Composite Thin Films for Potential Optical Sensing Applications

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