Synthesis, Optical Characterization, and Size Distribution Determination by Curve Resolution Methods of Water-Soluble CdSe Quantum Dots

Santos, Calink Indiara do Livramento; Carvalho, Melissa S.; Raphael, Ellen; Dantas, Clécio; Ferrari, Jefferson Luis; Schiavon, Marco A.

doi:10.1590/1980-5373-mr-2016-0121

Cited by 46 publications

(14 citation statements)

References 51 publications

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“…Various other elastic parameters, including stress and energy density, can also be calculated from the value of the intrinsic strain. There are various methods used for calculating and separating the crystallite size and lattice strain contributions to the peak broadening which include Warren–Averbach (W–A) analysis, Williamson–Hall (W–H) analysis, Balzar method, Fourier technique, and Rietveld refinement. − W–A and Balzar methods consider the Stokes Fourier deconvolution technique, and they are difficult to execute because they involve convolution of size and strain broadening. − The easiest and suitable method that can be used for the determination of average size and different elastic properties including stress, strain, energy density, and Young’s modulus is the W–H method because it only uses the full width at half maximum of the diffraction peak to calculate all these parameters . The synthesized CuSe nanoparticles have also been studied for their UV photodetection properties.…”

Section: Introductionmentioning

confidence: 99%

X-ray Diffraction Analysis of Hexagonal Klockmannite CuSe Nanoparticles for Photodetectors under UV Light

2021

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The CuSe nanoparticles are synthesized from direct vapor transport-grown CuSe compound using the sonochemical exfoliation technique. The chemical composition, crystalline phase, morphological analysis, optical properties, vibrational modes, and oxidation states of the elements of the synthesized nanoparticles are verified by energy-dispersive analysis of X-rays (EDAX), elemental mapping, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), ultraviolet diffused reflectance spectroscopy (UV-DRS) - photoluminescence measurements (PL), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Here, the particle sizes and the intrinsic strain of the XRD peak broadening analysis were investigated using the Williamson–Hall method (W–H), size–strain plot, and Halder–Wagner process (H–W). In addition, for the determination of physical and microstructural parameters such as strain, stress, and energy density, various models, that is, uniform deformation model, uniform stress deformation model, uniform deformation energy density model, have been well-thought-out in the W–H method. The average particle size calculated by the methods of W–H, size–strain, and H–W is compared to that calculated using HR-TEM and particle size analysis. Photodetectors based on CuSe nanoparticles are fabricated and studied under UV light with an on/off period of 10 s. The device showed excellent photoconductivity, photocurrent, responsivity, specific detectivity, external quantum efficiency, and good response time. The results demonstrated that CuSe nanoparticles possess excellent optoelectronic properties and have potential applications under UV light conditions.

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Section: Introductionmentioning

confidence: 99%

X-ray Diffraction Analysis of Hexagonal Klockmannite CuSe Nanoparticles for Photodetectors under UV Light

2021

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“…As shown in Fig. 4, this band disappeared in the case of the MPA-ZnS QDs and MPS-ZnS QDs, demonstrating the attachment of the MPA and MPS ligands through covalent bonds between thiols and surface Zn atoms of ZnS QDs [40].…”

Section: Ir Absorptionmentioning

confidence: 83%

ZnS quantum dots as fluorescence sensor for quantitative detection of tetracycline

et al. 2022

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“…Despite various in-depth studies on multicolor photoluminescence, 33 , 34 the origin of this phenomenon is still debatable. Up to now, no individual model can explain all aspects related to excitation-dependent emission.…”

Section: Resultsmentioning

confidence: 99%

Label-Free Iron Oxide Nanoparticles as Multimodal Contrast Agents in Cells Using Multi-Photon and Magnetic Resonance Imaging

Reynders¹,

Zundert²,

Silva³

et al. 2021

IJN

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Introduction The inherent fluorescence properties of iron oxide nanoparticles (IONPs) were characterized, and their applicability for multiphoton imaging in cells was tested in combination with their magnetic resonance imaging (MRI) capabilities. Methods Superparamagnetic iron oxide nanoparticles were synthesized and subsequently coated with polyethylene glycol to make them water-dispersible. Further characterization of the particles was performed using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), dynamic light scattering (DLS), superconducting quantum interference device (SQUID) and magnetic resonance relaxivity measurements. MRI and fluorescence properties of bare IONPs were first studied in solution and subsequently in A549-labeled cells. Results The particles, with a core size of 11.3 ± 4.5 nm, showed a good negative MRI contrast in tissue-mimicking phantoms. In vitro studies in mammalian A549 cells demonstrate that these IONPs are biocompatible and can also produce significant T2/T2* contrast enhancement in IONPs-labeled cells. Furthermore, excitation-wavelength dependent photoluminescence was observed under one- and two-photon excitation. Discussion The obtained results indicated that IONPs could be used for fluorescence label-free bioimaging at multiple wavelengths, which was proven by multiphoton imaging of IONPs internalization in A549 cancer cells.

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Synthesis, Optical Characterization, and Size Distribution Determination by Curve Resolution Methods of Water-Soluble CdSe Quantum Dots

Cited by 46 publications

References 51 publications

X-ray Diffraction Analysis of Hexagonal Klockmannite CuSe Nanoparticles for Photodetectors under UV Light

X-ray Diffraction Analysis of Hexagonal Klockmannite CuSe Nanoparticles for Photodetectors under UV Light

ZnS quantum dots as fluorescence sensor for quantitative detection of tetracycline

Label-Free Iron Oxide Nanoparticles as Multimodal Contrast Agents in Cells Using Multi-Photon and Magnetic Resonance Imaging

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