scholarly journals Studies of Nucleation Phase of Mn-doped Cadmium-Selenide (CdSe) Quantum Dots Via Photoluminescence Spectroscopy

2021 ◽  
Vol 1 (1) ◽  
pp. 64-70
Author(s):  
Nor Aliya Hamizi ◽  
Ahmad Bayhaki Sadidarto ◽  
Mohd Rafie Johan ◽  
Hairul Anuar Tajuddin ◽  
Zaira Zaman Chowdhury ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Cadmium Selenide ◽  
Reaction Temperature ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Physical Size ◽  
Pl Spectra ◽  
Different Temperatures ◽  
Nucleation Phase ◽  
Mn Doped

In this paper, we predict the nucleation phase of as-synthesized manganese (Mn) doped cadmium selenide (CdSe) quantum dots (QDs) at an intrinsic physical size of 3 (± 0.1 – 0.9) nm via photoluminescence (PL) studies. The nucleation phase was analyzed at temporal evolution (16, 46 and 90 mins) and temperature (210, 215 and 220 ºC) below the CdSe QDs reaction temperature (210 and 215 ºC) to it reaction temperature (220 ºC). The PL spectra`s observed to be against the QDs ripening behaviour of QDs since there are no prominent red-shift of PL spectra`s. However, the intensity of PL spectra`s shows to be varied with different temperatures and times.

scholarly journals Investigation on Surface Properties of Mn-Doped CdSe Quantum Dots Studied by X-ray Photoelectron Spectroscopy

Symmetry ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1250 ◽  
Author(s):  
Hamizi ◽  
Johan ◽  
Abdul Wahab ◽  
Chowdhury ◽  
Akbarzadeh Pivehzhani ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Binding Energy ◽  
Cadmium Selenide ◽  
Photoelectron Spectroscopy ◽  
Organic Ligand ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
X Ray ◽  
Inverse Micelle ◽  
Mn Doped

In this work, we report on the effects of incorporating manganese (Mn) dopant into different sizes of cadmium selenide (CdSe) quantum dots (QDs), which improves the electronic and optical properties of the QDs for multiple applications such as light-emitting diodes, lasers, and biological labels. Furthermore, the greener inverse Micelle method was implemented using organic ligand, which is oleic acid. This binding of the surface enhanced the QDs’ surface trap passivation of Mn-doped CdSe, which then increased the quantity of the output. In addition, the inverse Micelle technique was used successfully to dope Mn into CdSe QDs without the risk of Mn dopants being self-purified as experienced by wurtzite CdSe QDs. Also, we report the X-ray photoelectron spectroscopy (XPS) results and analysis of zinc blended manganese-doped cadmium selenide quantum dots (Mn-doped CdSe QDs), which were synthesized with physical sizes that varied from 3 to 14 nm using the inverse Micelle method. The XPS scans traced the existence of the Se 3d and Cd 3d band of CdSe crystals with a 54.1 and 404.5 eV binding energy. The traced 640.7 eV XPS peak is proof that Mn was integrated into the lattice of CdSe QDs. The binding energy of the QDs was related to the increase in the size of the QDs.

HIGHLY ORDERED MICRO-ARRAYS OF CdSe QUANTUM DOTS ON CHEMICALLY PATTERNED SUBSTRATES

2009 ◽  
Vol 08 (01n02) ◽  
pp. 119-122
Author(s):  
LI ZHANG ◽  
HUA-YAN SI ◽  
HUA XU ◽  
HAO-LI ZHANG ◽  
YU-QING XIONG
Keyword(s):  
Quantum Dots ◽  
Cadmium Selenide ◽  
Self Assembly ◽  
Microcontact Printing ◽  
Cdse Quantum Dots ◽  
Two Dimensional ◽  
Liquid Interfaces ◽  
Patterned Substrates ◽  
Cdse Qds ◽  
Ordered Arrays

Highly ordered arrays consisting uniform fluorescent cadmium selenide ( CdSe ) quantum dots (QDs) ring or dot structures were obtained by self-assembly of QDs on chemically patterned substrates. In this method, Au substrates with alternating hydrophobic and hydrophilic square patterns are firstly fabricated by microcontact printing, which allows water droplets to condense on the hydrophilic regions to provide two-dimensional template arrays. The CdSe QDs are then assembled at the liquid/liquid interfaces to give uniform micro or nanostructures. The shape and size of the rings and dots can be tailored by controlling the relative evaporation speed of the water and the organic solvents. The obtained nanostructures have ideal topography to avoid substrate-induced fluorescence quenching.

Europium doping of cadmium selenide (CdSe) quantum dots via rapid microwave synthesis for optoelectronic applications

2022 ◽  
Author(s):  
Donovan Thomas ◽  
Harold O. Lee ◽  
Kevin C. Santiago ◽  
Marvin Pelzer ◽  
Ayodeji Kuti ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Energy Transfer ◽  
Cadmium Selenide ◽  
Microwave Synthesis ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Europium Doping ◽  
Vis Spectroscopy ◽  
Tunable Optical Properties

UV-Vis spectroscopy and PL data show that structural incorporation of Eu3+ has an effect on the optical properties of CdSe QDs via energy transfer from host to dopant. This allows for QDs with tunable optical properties via numerous pathways.

scholarly journals Intense Visible Luminescence in CdSe Quantum Dots by Efficiency Surface Passivation with H2O Molecules

2012 ◽  
Vol 2012 ◽  
pp. 1-6
Author(s):  
Hyeoung Woo Park ◽  
Do-Hyung Kim
Keyword(s):  
Heat Treatment ◽  
Quantum Dots ◽  
Quantum Yield ◽  
Surface Passivation ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Effect Of Water ◽  
Visible Luminescence ◽  
Luminescence Efficiency

We have investigated the effect of water (H2O) cooling and heat treatment on the luminescence efficiency of core CdSe quantum dots (QDs). The photoluminescence (PL) quantum yield of the CdSe QDs was enhanced up to ~85%, and some periodic bright points were observed in wide color ranges during the heat treatment of QDs mixed with H2O. The PL enhancement of QDs could be attributed to the recovery of QDs surface traps by unreacted ligands confined within the hydrophilic H2O molecule containers.

Developed one-pot synthesis of dual-color CdSe quantum dots for white light-emitting diode application

2018 ◽  
Vol 6 (12) ◽  
pp. 3089-3096 ◽  
Author(s):  
Sheng Dai ◽  
Cyuan-Bin Siao ◽  
Shu-Ru Chung ◽  
Kuan-Wen Wang ◽  
Xiaoqing Pan
Keyword(s):  
Quantum Dots ◽  
White Light ◽  
Light Emitting Diode ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
One Pot ◽  
Synthetic Process ◽  
Light Emitting ◽  
One Pot Synthesis ◽  
Enhanced Stability

The size and fraction of red and green CdSe QDs can be controlled precisely during the synthetic process, thus manifesting remarkably enhanced stability.

PET-RAFT polymerization catalyzed by cadmium selenide quantum dots (QDs): Grafting-from QDs photocatalysts to make polymer nanocomposites

2020 ◽  
Vol 11 (5) ◽  
pp. 1018-1024 ◽  
Author(s):  
Yifan Zhu ◽  
Eilaf Egap
Keyword(s):  
Quantum Dots ◽  
Cadmium Selenide ◽  
Polymer Nanocomposites ◽  
Chain Transfer ◽  
Raft Polymerization ◽  
Cdse Qds ◽  
Reversible Addition ◽  
Cadmium Selenide Quantum Dots ◽  
Grafting From ◽  
Chain Transfer Polymerization

We report herein the first example of light-controlled radical reversible addition–fragmentation chain transfer polymerization facilitated by cadmium selenide quantum dots and the grafting-from CdSe QDs to create polymer-QDs nanocomposites.

Optimizing electron transfer from CdSe QDs to hydrogenase for photocatalytic H2 production

2019 ◽  
Vol 55 (39) ◽  
pp. 5579-5582 ◽  
Author(s):  
Monica L. K. Sanchez ◽  
Chang-Hao Wu ◽  
Michael W. W. Adams ◽  
R. Brian Dyer
Keyword(s):  
Quantum Dots ◽  
Electron Transfer ◽  
Reduction Potential ◽  
H2 Production ◽  
Cdse Quantum Dots ◽  
Redox Mediators ◽  
Cdse Qds ◽  
Electron Shuttles ◽  
Hydrogenase Enzyme

A series of viologen related redox mediators of varying reduction potential has been characterized and their utility as electron shuttles between CdSe quantum dots and hydrogenase enzyme has been demonstrated.

scholarly journals High Sensitivity Detection of Copper Ions in Oysters Based on the Fluorescence Property of Cadmium Selenide Quantum Dots

Chemosensors ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 47 ◽  
Author(s):  
Jiang ◽  
Lu ◽  
Su ◽  
Feng ◽  
Zhou ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Cadmium Selenide ◽  
Copper Ions ◽  
Synthesis Method ◽  
High Sensitivity ◽  
Absorption Spectrometry ◽  
Cdse Qds ◽  
Flame Atomic Absorption ◽  
Cadmium Selenide Quantum Dots ◽  
The One

Cadmium selenide (CdSe) quantum dots (QDs) were synthesized by water phase synthesis method using 3-mercaptopropionic acid (3-MPA) as a stabilizer, and they were applied to the detection of copper ions (Cu2+). The results showed that CdSe QDs have excellent selectivity and sensitivity toward Cu2+. The fluorescence intensity of CdSe QDs decreased with the increase of Cu2+ concentration. The linear range was from 30 nM to 3 μM, and the detection limit was 30 nM. Furthermore, CdSe QDs were used for detecting the concentration of Cu2+ in oysters. The content of Cu2+ was 40.91 mg/kg, which was close to the one measured via flame atomic absorption spectrometry (FAAS), and the relative error was 1.81%. Therefore, CdSe QDs have a wide application prospect in the rapid detection of copper ions in food.

Switching-on superparamagnetism in diluted magnetic Fe(iii) doped CdSe quantum dots

CrystEngComm ◽  
2020 ◽  
Vol 22 (10) ◽  
pp. 1738-1745 ◽  
Author(s):  
Amar Nath Yadav ◽  
Jasleen K. Bindra ◽  
Narendra Jakhar ◽  
Kedar Singh
Keyword(s):  
Quantum Dots ◽  
Exchange Interaction ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Ferromagnetic Exchange ◽  
Diluted Magnetic ◽  
Weak Ferromagnetic

Chemically prepared, 0.5% Fe(iii)-doped CdSe QDs exhibit superparamagnetism with weak ferromagnetic exchange interaction.

Dependence of Luminescence Efficiency of CdSe Quantum Dots on Chemical Environments

2008 ◽  
Vol 8 (11) ◽  
pp. 5615-5623 ◽  
Author(s):  
Rajan Jose ◽  
Mitsuru Ishikawa ◽  
Velmurugan Thavasi ◽  
Yoshinobu Baba ◽  
Seeram Ramakrishna
Keyword(s):  
Quantum Dots ◽  
Cadmium Acetate ◽  
Trioctylphosphine Oxide ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Luminescence Efficiency ◽  
Cadmium Stearate

Dependence of photoluminescence (PL) efficiency (ΦPL) of CdSe quantum dots (QDs) on coordinating solvents, precursors, and dispersing solvents was investigated. The ΦPL of CdSe QDs was ∼0.05 when synthesized at 120 °C using the precursors, cadmium acetate (CdAc) and trioctylphosphine selenide (TOPSe) in trioctylphosphine (TOP). The ΦPL was increased from 0.05 to ∼0.1 when coordinating solvents, trioctylphosphine oxide (TOPO) and hexadecylamine (HDA), were added to the above reaction mixture. The ΦPL was dramatically increased from ∼0.1 to ∼0.7 when CdAc was replaced by cadmium stearate (CdSt). The ΦPL of CdSe QDs synthesized using cadmium stearate (CdSt)/TOPSe/TOP/TOPO was measured in butanol, chloroform, hexane, and toluene and found that the ΦPL is strong dispersing solvent-dependent. The DFT analysis at b3lyp/lanl2dz level on the interaction of CdSe QDs with chemical environments showed that oxygen-containing molecules interact strongly with CdSe compared to non-oxygen containing molecules and could influence the ΦPL.

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