Room temperature synthesis of aqueous ZnCuInS/ZnS quantum dots

Nady, Jehan El; Ali, Magdy; Kamel, Ola A.; Ebrahim, Shaker; Soliman, Moataz

doi:10.1080/01932691.2019.1645022

Cited by 12 publications

(8 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The independent emission of CIS/ZnS QDs is attributed to the passivation of the CIS core with the ZnS shell. In addition, reduction of the surface defects via nonradiative recombination of electrons and holes is enhanced. , It was reported that the emission peak at 640 nm depends on the ratio Cu/In, and increasing the ratio of In shifted this peak to the blue region due to the diffusion of the small size of In into the core of CIS to reduce the particle size of the QDs …”

Section: Resultsmentioning

confidence: 99%

“…This can be explained based on the electron transfer process between the CIS/ZnS QDs and N-GQDs. The full width at half-maximum (FWHM) of the nanocomposite is calculated to be 98 nm, while that for N-GQDs is 80 nm that detects recombination in the hybrid structures of N-GQDs and CIS/ZnS QDs. − There are two approaches to quenching the emission of QDs. First, the N-GQDs are bound to the surface of the CIS/ZnS QDs and serve as ligands instead of MPA. − Second, the carboxylate groups in MPA are bonded with N-GQDs and lead to energy transfer between N-GQDs and CIS/ZnS QDs.…”

Section: Resultsmentioning

confidence: 99%

“…The full width at half-maximum (FWHM) of the nanocomposite is calculated to be 98 nm, while that for N-GQDs is 80 nm that detects recombination in the hybrid structures of N-GQDs and CIS/ZnS QDs. − There are two approaches to quenching the emission of QDs. First, the N-GQDs are bound to the surface of the CIS/ZnS QDs and serve as ligands instead of MPA. − Second, the carboxylate groups in MPA are bonded with N-GQDs and lead to energy transfer between N-GQDs and CIS/ZnS QDs. Consequently, N-GQDs can act as a capping agent with MPA on the CIS core. , The results thus suggest that a lower concentration of CIS/ZnS with 0.5 favors and produces an optimum fluorescence in the nanocomposite.…”

Section: Resultsmentioning

confidence: 99%

“…On the other hand, in a strong basic medium at pH 8 and 10, an increase in PL intensity is observed due to the deprotonation of carboxylate groups in CIS/ZnS QDs and N-GQDs. However, this forms an anionic double layer, disturbs the electron transfer between N-GQDs and CIS/ZnS QDs, and decreases the stability of the nanocomposites. − …”

Section: Resultsmentioning

confidence: 99%

“…According to biomolecules, the quenching effects of cholesterol and AA are strongly comparable to those of glucose and cholic acid, which quenched the nanocomposite emission by 46 and 32%, respectively. This is attributed to the presence of hydroxyl groups adsorbed on the surface of NG/CIS/ZnS QDs, and the excited electrons in the nanocomposite are transferred to AA, leading to quenching of the PL spectra of NG/CIS/ZnS QDs. − It can be concluded that there may be a slight interference of detection of cholesterol by the nanocomposite QDs with glucose and cholic acid.…”

Section: Resultsmentioning

confidence: 99%

See 4 more Smart Citations

Nanocomposite of CuInS/ZnS and Nitrogen-Doped Graphene Quantum Dots for Cholesterol Sensing

et al. 2021

Self Cite

View full text Add to dashboard Cite

In this paper, nitrogen graphene quantum dots (N-GQDs) and copper indium sulfide/zinc sulfide (CIS/ZnS) QDs were synthesized via facile hydrothermal and aqueous solution routes, respectively. Herein, a fluorescent nanocomposite has been synthesized between N-GQDs and CIS/ZnS QDs in an aqueous phase. This nanocomposite was characterized by photoluminescence, Raman, and ultraviolet–visible (UV–vis) spectroscopies, high-resolution transmission electron microscopy (HRTEM), and X-ray diffraction (XRD). This fluorescent nanocomposite was developed as a highly sensitive, selective nonenzymatic cholesterol optical biosensor in 0.312–5 mM cholesterol. HRTEM micrographs confirmed the preparation of CIS/ZnS QDs and N-GQDs with average diameters of 3 and 5 nm, respectively. The as-prepared NG/CIS/ZnS QD nanocomposite had a high sensitivity for cholesterol with a wide linear range of concentration of 0.312–5 mM with an excellent correlation coefficient (R 2) of 0.9688 and limit of detection (LOD) of 0.222 mM.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 3 more Smart Citations

Nanocomposite of CuInS/ZnS and Nitrogen-Doped Graphene Quantum Dots for Cholesterol Sensing

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

High Photoluminescence Polyindole/CuInS Quantum Dots for Pb Ions Sensor

Elkony

Ali

Ebrahim

et al. 2022

J Inorg Organomet Polym

View full text Add to dashboard Cite

Polyindole is considered an excellent conducting polymer with interested properties for different applications. A novel polyindole (PIn)/CuInS (CIS)/ZnS quantum dots (QDs) nanocomposite was synthesized via in situ polymerization of PIn in presence of CIS/ZnS QDs. By investigating the effect of CIS/ZnS QDs on optical properties of PIn, it was found that the optical band gaps of PIn, CIS/ZnS QDs, and PIn/CIS/ZnS QDs nanocomposite were 3.24 eV, 4.68 eV and 3.44 eV, respectively. From the luminance spectra, it was observed that emission peaks of PIn at 442 and 468 nm are independent of the excitation wavelength with the highest intensity at excitation wavelength of 380 nm. However, the luminance spectrum of PIn/CIS/ZnS QDs nanocomposite exhibited a quenching peak for CIS/ZnS QDs while the intensity of PIn peak was enhanced. High resolution of transmission electron microscope image of CIS/ZnS QDs revealed nanocrystals with a size of 3–4.5 nm and lattice space of 0.2 nm. PIn/CIS/ZnS QDs nanocomposite as the fluorescent probe was employed for sensing different concentrations of Pb2+ from 5 to 50 ppb. The reaction between PIn/CIS/ZnS QDs and Pb2+ was slightly quenched and fixed after 90 min. The emission peak was reduced gradually with increasing concentration of lead via photo-induced electron transfer or ion exchange mechanism. The value of correlation coefficient (R2) was 0.99, the sensitivity was 0.0041 ppb−1 and limit of detection value was 4.48 ppb.

show abstract

Glutathione-Capped ZnS Quantum Dots-Urease Conjugate as a Highly Sensitive Urea Probe

Metwly

Fadl

Soliman

et al. 2023

J Inorg Organomet Polym

Self Cite

View full text Add to dashboard Cite

Quantum dots (QDs) possess characteristic chemical and optical features. In this light, ZnS QDs capped with glutathione (GSH) were synthesized via an easy aqueous co-precipitation technique. Fabricated QDs were characterized in terms of X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM), Fourier transform infrared (FTIR) and Zeta potential analyses. Optical properties were examined using photoluminescence (PL) and ultraviolet–visible (UV–visible) spectroscopies. Moreover, GSH-capped ZnS QDs were evaluated as an optical probe for non-enzymatic detection of urea depending on the quenching of PL intensity of ZnS QDs in the presence of urea from concentration range of 0.5–5 mM with a correlation coefficient (R2) of 0.995, sensitivity of 0.0875 mM−1 and LOD of 0.426 mM. Furthermore, GSH-capped ZnS QDs-urease conjugate was utilized as an optical probe for enzymatic detection of urea in the range from 1.0 µM to 5.0 mM. Interestingly, it was observed that urea has a good affinity towards ZnS QDs-urease conjugate with a linear relationship between the change of PL intensity and urea concentration. It was found that R2 is 0.997 with a sensitivity of 0.042 mM−1 for mM concentration (0.5–5 mM) and LOD of 0.401 mM. In case of µM concentration range (1–100 µM), R2 was 0.971 with a sensitivity of 0.0024 µM−1 and LOD of 0.687 µM. These data suggest that enzyme conjugation to capped QDs might improve their sensitivity and applicability. Graphical Abstract

show abstract

Room temperature synthesis of aqueous ZnCuInS/ZnS quantum dots

Cited by 12 publications

References 36 publications

Nanocomposite of CuInS/ZnS and Nitrogen-Doped Graphene Quantum Dots for Cholesterol Sensing

Nanocomposite of CuInS/ZnS and Nitrogen-Doped Graphene Quantum Dots for Cholesterol Sensing

High Photoluminescence Polyindole/CuInS Quantum Dots for Pb Ions Sensor

Glutathione-Capped ZnS Quantum Dots-Urease Conjugate as a Highly Sensitive Urea Probe

Contact Info

Product

Resources

About