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.

Measuring photoluminescence spectra of self-assembly array nanowire of colloidal CdSe quantum dots using scanning near-field optics microscopy

2016 ◽  
Vol 09 (03) ◽  
pp. 1650040 ◽  
Author(s):  
Zhongchen Bai ◽  
Licai Hao ◽  
Zhengping Zhang ◽  
Shuijie Qin
Keyword(s):  
Quantum Dots ◽  
Self Assembly ◽  
Near Field ◽  
Porous Titanium ◽  
Periodic Array ◽  
Main Peak ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Near Field Optics ◽  
Assembly Method

A novel periodic array CdSe nanowire is prepared on a substrate of the porous titanium dioxide by using a self-assembly method of the colloidal CdSe quantum dots (QDs). The experimental results show that the colloidal CdSe QDs have renewedly assembled on its space scale and direction in process of losing background solvent and form the periodic array nanowire. The main peak wavelength of Photoluminescence (PL) spectra, which is measured by using a 100-nm aperture laser beam spot on a scanning near-field optics microscopy, has shifted 60 nm with compared to the colloidal CdSe QDs. Furthermore, we have measured smaller ordered nanometer structure in thin QDs area as well, a 343-nm periodic nanowire in thick QDs area and the colloidal QDs in edge of well-ordered nanowire.

scholarly journals Spontaneous Emission Enhancement of CdSe Quantum Dots Embedded in a Two-dimensional Photonic Crystal L3 Nanocavity

2021 ◽  
Vol 9 (2) ◽  
pp. 38-41
Author(s):  
Khalid N. Sediq
Keyword(s):  
Quantum Dots ◽  
Photonic Crystal ◽  
Spontaneous Emission ◽  
Quantum Electrodynamics ◽  
Cavity Quantum Electrodynamics ◽  
Cdse Quantum Dots ◽  
Two Dimensional ◽  
Cdse Qds ◽  
Dimensional Photonic Crystal ◽  
Two Dimensional Photonic Crystal

Two-dimensional photonic crystal nanocavities were designed to tailor cavity quantum electrodynamics. Enhancing the spontaneous emission of low-quality factor nanocavity with embedded CdSe quantum dots (QDs) emitters is the aim of this study. Low concentration layer of CdSe QDs was sandwiched between two layers of Si2 N3 membrane using plasma-enhanced chemical vapor deposition. The modification rate in spontaneous emission of L3 nanocavity up to 2.3-fold has been observed at 629.5 nm in compare to bare cavities. High field confinement in the sub-wavelength regime became an interest field for quantum electrodynamics applications and good platform to study light matter interactions.

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.

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.

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.

Transparent and Light-Emitting Epoxy Nanocomposites Filled with Dodecylamine-Capped CdSe Quantum Dots

2015 ◽  
Vol 727-728 ◽  
pp. 284-287
Author(s):  
Ling Ling Chen
Keyword(s):  
Quantum Dots ◽  
Self Assembly ◽  
Epoxy Matrix ◽  
Visible Region ◽  
Cdse Quantum Dots ◽  
Cdse Qds ◽  
Epoxy Nanocomposites ◽  
Light Emitting ◽  
Homogeneous Dispersion ◽  
Carbon Chains

An effective approach was used to disperse CdSe quantum dots (QDs) into epoxy matrix and prepare highly transparent luminescent CdSe–epoxy nanocomposites. Dodecylamine-capped CdSe QDs were obtained through self-assembly of carbon chains of as-synthesized QDs and dodecylamine. It was found that dodecylamine-capped CdSe QDs demonstrate a homogeneous dispersion within epoxy matrix, thus the prepared CdSe–epoxy nanocomposites expressed transparence in the visible region and also light-emitting.

scholarly journals Exploring size and state dynamics in CdSe quantum dots using two-dimensional electronic spectroscopy

2014 ◽  
Vol 140 (8) ◽  
pp. 084701 ◽  
Author(s):  
Justin R. Caram ◽  
Haibin Zheng ◽  
Peter D. Dahlberg ◽  
Brian S. Rolczynski ◽  
Graham B. Griffin ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Electronic Spectroscopy ◽  
Cdse Quantum Dots ◽  
Two Dimensional

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.

Sign in / Sign up

Export Citation Format

Share Document