Proton Irradiation Effects on Colloidal InGaP/ZnS Core–Shell Quantum Dots Embedded in Polydimethylsiloxane: Discriminating Core from Shell Radiation-Induced Defects through Time-Resolved Photoluminescence Analysis

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.

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Time-Resolved Photoluminescence Study of MnS/ZnS Core/Shell Quantum Dots at High Pressure and Low Temperature

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.1c07179 ◽

2021 ◽

Vol 125 (40) ◽

pp. 22354-22359

Author(s):

Da Huang ◽

He Wang ◽

Wei Zhao ◽

Rucheng Dai ◽

Zhongping. Wang ◽

...

Keyword(s):

Quantum Dots ◽

High Pressure ◽

Low Temperature ◽

Core Shell ◽

Time Resolved ◽

Photoluminescence Study ◽

Time Resolved Photoluminescence

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Time Resolved Studies of Proton Irradiated Quantum Dots

MRS Proceedings ◽

10.1557/proc-722-k11.6 ◽

2002 ◽

Vol 722 ◽

Author(s):

Saulius Marcinkevičius ◽

Rosa Leon ◽

Charlene Lobo ◽

Brian Magness ◽

William Taylor

Keyword(s):

Quantum Dots ◽

Quantum Wells ◽

Proton Irradiation ◽

Three Dimensional ◽

Carrier Dynamics ◽

Time Resolved ◽

Carrier Lifetimes ◽

Dot Density ◽

Gaas Quantum Dot ◽

Time Resolved Photoluminescence

AbstractThe effects of proton irradiation on carrier dynamics were measured by time-resolved photoluminescence on InGaAs/GaAs quantum dot structures with different dot density and substrate orientation, as well as on InAlAs/AlGaAs quantum dots. Results were compared to irradiation effects on carrier dynamics in thin InGaAs quantum wells. We find that carrier lifetimes in QDs are much less affected by proton irradiation than in quantum wells, which can be attributed to the three-dimensional carrier confinement in quantum dots.

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Highly fluorescent CsPbBr3/TiO2 core/shell perovskite nanocrystals with excellent stability

SN Applied Sciences ◽

10.1007/s42452-021-04648-8 ◽

2021 ◽

Vol 3 (6) ◽

Author(s):

Haitao Chen ◽

Renhua Li ◽

Anqi Guo ◽

Yu Xia

Keyword(s):

Identical Particle ◽

Core Shell ◽

List Type ◽

Easy Method ◽

Time Resolved ◽

Perovskite Nanocrystals ◽

Promising Application ◽

The Stability ◽

Time Resolved Photoluminescence ◽

Excellent Stability

AbstractThe poor stability of CsPbX3 (X = Cl, Br, I) perovskite nanocrystals is the most impediment to its application in the field of photoelectrics. In this work, monodisperse CsPbBr3/TiO2 nanocrystals are successfully prepared by coating titanium precursor on the surface of colloidal CsPbBr3 nanocrystals at room temperature. The CsPbBr3/TiO2 nanocomposites exhibit excellent stability, remaining the identical particle size (9.2 nm), crystal structures and optical properties. Time-resolved photoluminescence decay shows that the lifetime of CsPbBr3/TiO2 nanocrystals is about 4.04 ns and keeps great stability after lasting two months in the air. Results show that the coating of TiO2 on CsPbBr3 NCs greatly suppressed the anion exchange and photodegradation, which are the main reasons for dramatically improving their chemical stability and photostability. The results provide an effective method to solve the stability problem of perovskite nanostructures and are expected to have a promising application in optoelectronic fieldsArticle highlights 1. Prepared the all-inorganic CsPbBr3/TiO2 core/shell perovskite nanocrystals by an easy method. 2. Explored its essences of PL and lifetime of the synthesized CsPbBr3/TiO2 perovskite nanocrystals. 3. CsPbBr3/TiO2 nanocrystals show the great thermal stability after the post-annealing. 4. The CsPbBr3/TiO2 nanocrystals have a high PLQY and have a promising application in solar cells.

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