Effect of Charge Transferring Materials on Photoluminescence Properties of CdSe/ZnS Quantum Dots

2014 ◽  
Vol 981 ◽  
pp. 879-882
Author(s):  
Xuan Lin Chen ◽  
Yu Qiu Qu ◽  
Gui Fan Li ◽  
Hong Wei ◽  
Liu Yang Zhang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Absorption Spectrometry ◽  
Oxidation Potential ◽  
Dynamic Quenching ◽  
Photoluminescence Properties ◽  
Time Resolved ◽  
Transmission Electron ◽  
Quenching Efficiency ◽  
Quenching Process ◽  
Pl Quenching

The CdSe/ZnS core/shell quantum dots (QDs) were synthesized and characterized with absorption spectrometry, photoluminescence (PL) spectrometry and transmission electron microscopy. PL quenching of colloidal CdSe/ZnS QDs in the presence of charge transferring material was studied by means of steady-state and time-resolved PL spectroscopy. With increasing charge transferring materials concentration in the CdSe/ZnS QDs solution, the PL intensity and lifetime of CdSe/ZnS QDs decrease gradually. The quenching efficiency of CdSe/ZnS QDs decrease with increasing the oxidation potential of charge transferring materials. Based on the analysis, there are two pathways in the PL quenching process: static quenching and dynamic quenching. The dynamic quenching is correlated with hole transfer from QDs to the charge transferring materials.

scholarly journals Investigation on photoluminescence quenching of CdSe/ZnS quantum dots by organic charge transporting materials

2015 ◽  
Vol 33 (4) ◽  
pp. 709-713 ◽  
Author(s):  
Qu Yuqiu ◽  
Zhang Liuyang ◽  
An Limin ◽  
Wei Hong
Keyword(s):  
Quantum Dots ◽  
Oxidation Potential ◽  
Core Shell ◽  
Photoluminescence Intensity ◽  
Dynamic Quenching ◽  
Photoluminescence Quenching ◽  
Time Resolved ◽  
Quenching Efficiency ◽  
Hole Transporting ◽  
Time Resolved Photoluminescence

AbstractThe effect of different organic charge transporting materials on the photoluminescence of CdSe/ZnS core/shell quantum dots has been studied by means of steady-state and time-resolved photoluminescence spectroscopy. With an increase in concentration of the organic charge transporting material in the quantum dots solutions, the photoluminescence intensity of CdSe/ZnS quantum dots was quenched greatly and the fluorescence lifetime was shortened gradually. The quenching efficiency of CdSe/ZnS core/shell quantum dots decreased with increasing the oxidation potential of organic charge transporting materials. Based on the analysis, two pathways in the photoluminescence quenching process have been defined: static quenching and dynamic quenching. The dynamic quenching is correlated with hole transporting from quantum dots to the charge transporting materials.

Steady state and time resolved photoluminescence properties of CuInS2/ZnS quantum dots in solutions and in solid films

2015 ◽  
Vol 167 ◽  
pp. 333-338 ◽  
Author(s):  
Nikolaos Droseros ◽  
Kostas Seintis ◽  
Mihalis Fakis ◽  
Spiros Gardelis ◽  
Androula G. Nassiopoulou
Keyword(s):  
Quantum Dots ◽  
Steady State ◽  
Photoluminescence Properties ◽  
Time Resolved ◽  
Solid Films ◽  
Time Resolved Photoluminescence

scholarly journals Size-Dependent Non-FRET Photoluminescence Quenching in Nanocomposites Based on Semiconductor Quantum Dots CdSe/ZnS and Functionalized Porphyrin Ligands

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Eduard I. Zenkevich ◽  
Thomas Blaudeck ◽  
Alexander Milekhin ◽  
Christian von Borczyskowski
Keyword(s):  
Quantum Dots ◽  
Charge Transfer ◽  
Semiconductor Quantum Dots ◽  
Trap States ◽  
Quenching Rate ◽  
Time Resolved ◽  
Exciton Wave Function ◽  
Electron Hole Pair ◽  
Colloidal Semiconductor ◽  
Pl Quenching

We review recent experimental work to utilize the size dependence of the luminescence quenching of colloidal semiconductor quantum dots induced by functionalized porphyrin molecules attached to the surface to describe a photoluminescence (PL) quenching process which is different from usual models of charge transfer (CT) or Foerster resonant energy transfer (FRET). Steady-state and picosecond time-resolved measurements were carried out for nanocomposites based on colloidal CdSe/ZnS and CdSe quantum dots (QDs) of various sizes and surfacely attached tetra-mesopyridyl-substituted porphyrin molecules (“Quantum Dot-Porphyrin” nanocomposites), in toluene at 295 K. It was found that the major part of the observed strong quenching of QD PL in “QD-Porphyrin” nanocomposites can neither be assigned to FRET nor to photoinduced charge transfer between the QD and the chromophore. This PL quenching depends on QD size and shell and is stronger for smaller quantum dots: QD PL quenching rate constants scale inversely with the QD diameter. Based on the comparison of experimental data and quantum mechanical calculations, it has been concluded that QD PL quenching in “QD-Porphyrin” nanocomposites can be understood in terms of a tunneling of the electron (of the excited electron-hole pair) followed by a (self-) localization of the electron or formation of trap states. The major contribution to PL quenching is found to be proportional to the calculated quantum-confined exciton wave function at the QD surface. Our findings highlight that single functionalized molecules can be considered as one of the probes for the complex interface physics and dynamics of colloidal semiconductor QD.

Photoluminescence properties of transition metal-doped Zn–In–S/ZnS core/shell quantum dots in solid films

RSC Advances ◽  
2016 ◽  
Vol 6 (50) ◽  
pp. 44859-44864 ◽  
Author(s):  
Jiaming Li ◽  
Yang Liu ◽  
Jie Hua ◽  
Lianhua Tian ◽  
Jialong Zhao
Keyword(s):  
Quantum Dots ◽  
Steady State ◽  
Transition Metal ◽  
Metal Ion ◽  
Core Shell ◽  
Photoluminescence Properties ◽  
Time Resolved ◽  
Pl Spectra ◽  
Solid Films ◽  
Metal Doped

The photoluminescence (PL) properties of transition metal ion (Mn2+ or Cu+) doped Zn–In–S/ZnS core/shell quantum dots (QDs) in solution and solid films were investigated by using steady-state and time-resolved PL spectra.

The Structural and Optical Properties of Self-assembled InGaN/GaN Quantum Dots Grown by Molecular Beam Epitaxy

2006 ◽  
Vol 955 ◽  
Author(s):  
Tim Michael Smeeton ◽  
Mathieu Sénès ◽  
Katherine L Smith ◽  
Stewart E Hooper ◽  
Jon Heffernan
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Light Emission ◽  
Structural And Optical Properties ◽  
Discrete Energy ◽  
Time Resolved ◽  
Transmission Electron ◽  
Z Contrast

ABSTRACTThe structural and optical properties of InGaN quantum dots grown by plasma-assisted molecular beam epitaxy (MBE) have been characterised using atomic force microscopy, high-resolution transmission electron microscopy (TEM), Z-contrast scanning TEM, micro-photoluminescence (PL), temperature dependent PL and time-resolved PL. The uncapped InGaN nano-islands have densities of ∼1.5 × 1011 cm−2, heights of (1.7 ± 1.0) nm and diameters of (10 ± 4) nm. These parameters are not substantially changed during overgrowth of a GaN cap and the resulting quantum dots have a composition of In0.15Ga0.85N. The observation of narrow luminescence peaks in micro-PL measurements proves light emission from discrete energy states and the optical properties indicate strong confinement of carriers in the quantum dots and an unusually weak impact of piezoelectric field effects.

Scalable Non-injection Synthesis of Cd-Free Copper Indium Sulfide/Zinc Sulfide Quantum Dots for Third-Gen Photovoltaic Application

MRS Advances ◽  
2016 ◽  
Vol 1 (30) ◽  
pp. 2193-2198 ◽  
Author(s):  
Yaxin Zheng ◽  
Bahareh Sadeghimakki ◽  
Navid. M. S. Jahed ◽  
Siva Sivoththaman
Keyword(s):  
Quantum Dots ◽  
Stokes Shift ◽  
Emission Spectra ◽  
Indium Sulfide ◽  
Time Resolved ◽  
Photovoltaic Application ◽  
Transmission Electron ◽  
Copper Indium ◽  
Potential Applicability ◽  
Cadmium And Lead

ABSTRACTCopper Indium Sulfide (CIS)-based quantum dots (QDs) are considered as a safer alternative compared to carcinogenic cadmium- and lead-based QDs. Here, we present a facile, high throughput, and non-injection method of synthesizing CIS-based QDs. The structure, shape, size, and crystalline structure of the synthesized QDs were studied using high resolution transmission electron microscopy (HRTEM). The effects of temperature and compositional dependency on the structure and optical properties of the resulting QDs were investigated using elemental, absorption, photoluminescence (PL), and time-resolved spectroscopic analyses. We observed that a gradient increase of temperature during the core growth, as well as addition of excess indium (In) and zinc (Zn) precursors during core and core/shell synthesis, at low growth temperatures, resulted in QDs with improved PL and lifetime. The large Stokes shift, broad emission spectra, and long-lived emission of the synthesized QDs reveal their potential applicability to third generation photovoltaic and optoelectronic devices.

scholarly journals Luminescent properties of colloidal mixtures of Zn0.5Cd0.5S quantum dots and gold nanoparticles

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Oleg V. Ovchinnikov ◽  
Mikhail S. Smirnov ◽  
Irina G. Grevtseva ◽  
Violetta N. Derepko ◽  
Tamara A. Chevychelova ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Luminescent Properties ◽  
Sio2 Nanoparticles ◽  
Colloidal Synthesis ◽  
Luminescence Spectroscopy ◽  
Time Resolved ◽  
Exciton Coupling ◽  
Sio2 Shell ◽  
Transmission Electron ◽  
Investigation Methods

The aim of the study is to establish spectral-luminescent interaction effects in mixtures of colloidal Zn0.5Cd0.5S quantum dots passivated with 2-mercaptopropionic acid and Au and Au/SiO2nanoparticles. The studied samples of Zn0.5Cd0.5S quantum dots, Au and Au/SiO2 nanoparticles and their mixtures were obtained by methods of colloidal synthesis and were characterised using transmission electron microscopy. The absorption, luminescence and time-resolved luminescence spectroscopy were used as the main investigation methods. The measurements were carried out at temperatures of 77 K and 300 K. The spectral-luminescent properties of “free” Zn0.5Cd0.5S quantum dots and those interacting with Au and Au/SiO2 nanoparticles were compared. It was found that the luminescence properties of Zn0.5Cd0.5S quantum dots can be controlled under conditions of changing plasmon-exciton coupling achieved during the formation of a dielectric SiO2 shell  on the surface of Au nanoparticles as well as a result of a polymer introduced into the colloidal mixture.

Synthesis and Photoluminescence of ZnS Quantum Dots

2008 ◽  
Vol 8 (3) ◽  
pp. 1312-1315 ◽  
Author(s):  
Yu Hua Wang ◽  
Zhong Chen ◽  
Xiao Qun Zhou
Keyword(s):  
Quantum Dots ◽  
Ph Value ◽  
Broad Band ◽  
Surface States ◽  
Average Diameter ◽  
Zinc Sulphide ◽  
Photoluminescence Properties ◽  
Strong Broad Band ◽  
Zinc Blende ◽  
Transmission Electron

Single-phase zinc sulphide (ZnS) quantum dots were synthesized by a chemical method. The influence of the pH value of the Zn(CH3COO)2 solution on the size and photoluminescence properties of the ZnS quantum dots was evaluated. X-ray power diffraction, transmission electron microscopy, and ultraviolet-visible spectroscopy were used to characterize the structure, size, surface states, and photoluminescence properties of ZnS quantum dots. The results showed that the crystal structure of ZnS quantum dots was a cubic zinc blende structure, and their average diameter was about 3.0 nm. ZnS quantum dots with good distribution and high purity were obtained. A strong broad band centered at about 320 nm was observed in the excitation spectrum of ZnS quantum dots. Their emission spectrum peaking at about 408 nm, was due mostly to the trap-state emission. The relative integrated emission intensity of ZnS quantum dots decreased as the pH value of the Zn(CH3COO)2 solution increased, which could be ascribed to the increase in average diameter of the ZnS quantum dots as the pH value of Zn(CH3COO)2 solution increased.

Photoluminescence quenching and electron transfer in CuInS2/ZnS core/shell quantum dot and FePt nanoparticle blend films

RSC Advances ◽  
2015 ◽  
Vol 5 (39) ◽  
pp. 30981-30988 ◽  
Author(s):  
Jie Hua ◽  
Haibo Cheng ◽  
Xi Yuan ◽  
Yan Zhang ◽  
Mei Liu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Electron Transfer ◽  
Steady State ◽  
Magnetic Nanoparticles ◽  
Quantum Dot ◽  
Core Shell ◽  
Photoluminescence Quenching ◽  
Time Resolved ◽  
Blend Films ◽  
Pl Quenching

The photoluminescence (PL) quenching of CuInS2/ZnS quantum dots (QDs) in blend films with FePt magnetic nanoparticles (MNs) was studied by steady-state and time-resolved PL spectroscopy.

Sign in / Sign up

Export Citation Format

Share Document