Assessing the Environmental Effects Related to Quantum Dot Structure, Function, Synthesis and Exposure

2021 ◽  
Author(s):  
Marissa Giroux ◽  
Zahra Zahra ◽  
Omobayo Adio Salawu ◽  
Robert M. Burgess ◽  
Kay T. Ho ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Quantum Dot ◽  
Structure Function ◽  
Environmental Effects ◽  
Quantum Confinement ◽  
Semiconductor Nanocrystals

Quantum dots (QDs) are engineered semiconductor nanocrystals with unique fluorescent, quantum confinement, and quantum yield properties, making them valuable in a range of commercial and consumer imaging, display, and lighting...

Quantum Confinement in the Spectral Response of n-Doped Germanium Quantum Dots Embedded in an Amorphous Si Layer for Quantum Dot-Based Solar Cells

2020 ◽  
Vol 3 (3) ◽  
pp. 2813-2821
Author(s):  
Jacopo Parravicini ◽  
Francesco Di Trapani ◽  
Michael D. Nelson ◽  
Zachary T. Rex ◽  
Ryan D. Beiter ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Solar Cells ◽  
Quantum Dot ◽  
Quantum Confinement ◽  
Spectral Response ◽  
Amorphous Si ◽  
Germanium Quantum Dots

Polysalt ligands achieve higher quantum yield and improved colloidal stability for CsPbBr3 quantum dots

Nanoscale ◽  
2021 ◽  
Author(s):  
Sisi Wang ◽  
Liang Du ◽  
Selin Donmez ◽  
Yan Xin ◽  
Hedi Mattoussi
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Colloidal Stability ◽  
Semiconductor Nanocrystals ◽  
Perovskite Quantum Dots ◽  
Halide Perovskite ◽  
Colloidal Lead ◽  
Optoelectronic Applications ◽  
Cspbbr3 Quantum Dots ◽  
Lead Halide

Colloidal lead halide perovskite quantum dots (PQDs) are relatively new semiconductor nanocrystals with great potential for use in optoelectronic applications.

Quantum Dot-Sensitized Solar Cells via Integrated Experimental and Modeling Study

2019 ◽  
Vol 16 (2) ◽  
pp. 436-440
Author(s):  
Lekshmi Gangadhar ◽  
Anusha Kannan ◽  
P. K. Praseetha
Keyword(s):  
Quantum Dots ◽  
Solar Cells ◽  
Solar Cell ◽  
Quantum Dot ◽  
Low Cost ◽  
Semiconductor Nanocrystals ◽  
Green Energy ◽  
Research Areas ◽  
Sensitized Solar Cells ◽  
Modeling Study

The solar energy is one of the potential renewable green energy source considering the availability of sunlight in abundance and the need for clean and renewable source of energy. Quantum dots are semiconductor nanocrystals having considerable interest in photovoltaic research areas. Cadmium sulfide-sensitized solar cells are synthesized by Chemical bath deposition and titanium nanowires were fabricated by hydrothermal method. The synthesized CdS quantum dots are sensitized to nanoporous TiO2 films to form quantum dots-sensitized solar cell applications. The introduction of TNWs enables the electrolyte to penetrate easily inside the film which increases the interfacial contact between the nanowires, the quantum dots and the electrolyte results in improvement in efficiency of solar cell. The goal of our research is to understand the fundamental physics and performance of quantum dot-sensitized solar cells with improved photoconversion efficiency at the low cost based on selection of TiO2 nanostructures, sensitizers and electrodes through an integrated experimental and modeling study.

THE INFLUENCE OF ENVIRONMENTAL EFFECTS ON THE ACOUSTIC PHONON SPECTRA IN QUANTUM-DOT HETEROSTRUCTURES

2002 ◽  
Vol 12 (04) ◽  
pp. 1147-1158 ◽  
Author(s):  
SALVADOR RUFO ◽  
MITRA DUTTA ◽  
MICHAEL A. STROSCIO
Keyword(s):  
Quantum Dots ◽  
Quantum Dot ◽  
Environmental Effects ◽  
Phonon Spectrum ◽  
Acoustic Phonon ◽  
Matrix Material ◽  
Free Standing ◽  
Phonon Spectra ◽  
The Matrix ◽  
Selection Of

We present calculations of the acoustic phonon spectra for a variety of quantum dots and consider the cases where the quantum dots are both free-standing and embedded in a selection of different matrix materials — including semiconductors, plastic, and water. These results go beyond previous calculations for free-standing quantum dots and demonstrate that the matrix material can have a large effect on the acoustic phonon spectrum and consequently on a variety of phonon-assisted transitions in quantum-dot heterostructures.

Photoluminescent carbon–nitrogen quantum dots as efficient electrocatalysts for oxygen reduction

Nanoscale ◽  
2015 ◽  
Vol 7 (5) ◽  
pp. 2003-2008 ◽  
Author(s):  
Jianhua Shen ◽  
Yunfeng Li ◽  
Yunhe Su ◽  
Yihua Zhu ◽  
Hongliang Jiang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Catalytic Activity ◽  
Quantum Yield ◽  
Quantum Dot ◽  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Reduction Reaction ◽  
Electrochemical Measurements

A novel carbon–nitrogen quantum dot (CNQD) with a quantum yield of ca. 31% at 365 nm possesses the co-existence of both p- and n-type conductivities and the electrochemical measurements reveal that CNQDs exhibit catalytic activity for the oxygen reduction reaction.

scholarly journals Quantum dot probes for cellular analysis

2017 ◽  
Vol 9 (18) ◽  
pp. 2621-2632 ◽  
Author(s):  
Dahai Ren ◽  
Bin Wang ◽  
Chen Hu ◽  
Zheng You
Keyword(s):  
Quantum Dots ◽  
Quantum Dot ◽  
Semiconductor Nanocrystals ◽  
Pivotal Role ◽  
Biological Applications ◽  
Cellular Analysis

Highly fluorescent and robust semiconductor nanocrystals (known as quantum dots or QDs) play a pivotal role in biological applications.

Fabrication of high quantum yield quantum dot/polymer films by enhancing dispersion of quantum dots using silica particles

2013 ◽  
Vol 393 ◽  
pp. 74-79 ◽  
Author(s):  
Hyun Chang Kim ◽  
Hyun-Guk Hong ◽  
Cheolsang Yoon ◽  
Hoon Choi ◽  
Ik-Sung Ahn ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Quantum Dot ◽  
Polymer Films ◽  
Silica Particles ◽  
High Quantum Yield ◽  
High Quantum

scholarly journals Tuning the Emission Color of Hydrothermally Synthesized Carbon Quantum Dots by Precursor Engineering

2019 ◽  
Vol 35 (1) ◽  
Author(s):  
Mai Xuan Dung ◽  
Mai Van Tuan ◽  
Pham Truong Long ◽  
Nguyen Thi Mai
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Citric Acid ◽  
Quantum Yield ◽  
Quantum Dot ◽  
Carbon Dots ◽  
Carbon Quantum Dots ◽  
Water Soluble ◽  
Silicon Quantum Dots ◽  
Emission Quantum Yield

Water-soluble, biocompatible, and highly luminescence carbon quantum dots (CQDs) have synthesized successfully from a citric acid (CA) and ethylenediamine (EDA) by using different approaches. Although the emission quantum yield of CQDs could be as high as 80% their emission spectrum is usually dominated by surface fluorophore groups and maximized at about 450 nm. Herein, we examined the effects of acid and amine precursors on the photoluminescence (PL) of resulting CQDs by systematic comparison the optical properties of CQDs obtained from CA, PA (phthalic acid) and EDA, ANL (aniline). UV-vis and PL spectroscopic studies revealed that the absorption onset varied from 325 nm to 400 nm while PL maximum changed from 390 nm to 450 nm by engineering acid and amine precursors. The emission quantum yield was also changed from 9 to 70%, depending on the used acid-amine precursors.  Keywords Carbon quantum dots, hydrothermal synthesis, color tuning, photoluminescence, acid, amine References K. Wang, Z. Gao, G. Gao, Y. Wo, Y. Wang, G. Shen, D. Cui, Systematic safety evaluation on photoluminescent carbon dots, Nanoscale Res. Lett. 8 (2013) 1–9. doi:10.1186/1556-276X-8-122.[2] K. Jiang, S. Sun, L. Zhang, Y. Lu, A. Wu, C. Cai, H. Lin, Red, Green, and Blue Luminescence by Carbon Dots: Full-Color Emission Tuning and Multicolor Cellular Imaging, Angew. Chemie Int. Ed. 54 (2015) 5360–5363. doi:10.1002/anie.201501193.[3] M.X. Dung, P. Mohapatra, J.K. Choi, J.H. Kim, S. Jeong, H.D. Jeong, InP quantum dot-organosilicon nanocomposites, Bull. Korean Chem. Soc. 33 (2012) 1491–1504. doi:10.5012/bkcs.2012.33.5.1491.[4] X. Mai, Q. Hoang, The Large-Scale Synthesis of Vinyl-Functionalized Silicon Quantum Dot and Its Application in Miniemulsion Polymerization, J. Nanomater. 2016 (2016).[5] M.X. Dung, D.D. Tung, S. Jeong, H.D. Jeong, Tuning optical properties of Si quantum dots by ??-conjugated capping molecules, Chem. - An Asian J. 8 (2013) 653–664. doi:10.1002/asia.201201099.[6] M.X. Dung, H.D. Jeong, Synthesis of styryl-terminated silicon quantum dots: Reconsidering the use of methanol, Bull. Korean Chem. Soc. 33 (2012) 4185–4187.doi:10.5012/bkcs.2012.33.12.4185.[7] V.-T. Mai, N.H. Duong, X.-D. Mai, Surface Polarity Controls the Optical Properties of One-Pot Synthesized Silicon Quantum Dots, Chem. Phys. (2018).doi:10.1016/j.chemphys.2018.11.012.[8] V.-T. Mai, Q. Hoang, X. Mai, Enhanced Red Emission in Ultrasound-Assisted Sol-Gel Derived ZnO/PMMA Nanocomposite, Adv. Mater. Sci. Eng. 2018 (2018) 1–8. doi:10.1155/2018/7252809.[9] J. Schneider, C.J. Reckmeier, Y. Xiong, M. Von Seckendorff, A.S. Susha, P. Kasak, A.L. Rogach, Molecular fluorescence in citric acid-based carbon dots, J. Phys. Chem. C. 121 (2017) 2014–2022. doi:10.1021/acs.jpcc.6b12519.[10] F. Ehrat, S. Bhattacharyya, J. Schneider, A. Löf, R. Wyrwich, A.L. Rogach, J.K. Stolarczyk, A.S. Urban, J. Feldmann, Tracking the Source of Carbon Dot Photoluminescence: Aromatic Domains versus Molecular Fluorophores, Nano Lett. 17 (2017) 7710–7716. doi:10.1021/acs.nanolett.7b03863.[11] M. Shamsipur, A. Barati, A.A. Taherpour, M. Jamshidi, Resolving the Multiple Emission Centers in Carbon Dots: From Fluorophore Molecular States to Aromatic Domain States and Carbon-Core States, J. Phys. Chem. Lett. 9 (2018) 4189–4198. doi:10.1021/acs.jpclett.8b02043.[12] T.H.T. Xuan-Dung Mai, Quang-Bac Hoang, Hong Quan To, Phuong Le Thi, The synthesis of highly luminescent carbon quantum dots, (2017) (47)20-26.[13] M.X.D. Lê Thị Phượng, Lê Quang Trung, Đỗ Thị Thu Hòa, Doãn Diệu Thúy, Ảnh hưởng của tỷ lệ Acid/Amine đến cấu trúc bề mặt và hiệu suất phát xạ của chấm lượng tử carbon, (2018) (55) 67-74.[14] M.V.T. Hoàng Quang Bắc, Trần Thu Hương, Đinh Thị Châm, Nguyễn Thị Loan, Nguyễn Thị Quỳnh, Bùi Thị Huệ, Lê Thị Thùy Hương, Mai Xuân Dũng, Nghiên cứu tổng hợp hạt nano huỳnh quang từ một số rau củ quả, (2017) 4(40), 70-73.[15] Y. Song, S. Zhu, S. Zhang, Y. Fu, L. Wang, X. Zhao, B. Yang, Investigation from chemical structure to photoluminescent mechanism: a type of carbon dots from the pyrolysis of citric acid and an amine, J. Mater. Chem. C. 3 (2015) 5976–5984. doi:10.1039/C5TC00813A.[16] T.H. Ngà, B.T. Hạnh, M.X. Dũng, Tính toán lượng tử làm rõ tính chất quang học của chấm lượng tử carbon, Tạp Chí KHoa Học - Đại Học Sư Phạm Hà Nội 2. 56 (2018).[17] S. Zhu, Q. Meng, L. Wang, J. Zhang, Y. Song, H. Jin, K. Zhang, H. Sun, H. Wang, B. Yang, Highly photoluminescent carbon dots for multicolor patterning, sensors, and bioimaging, Angew. Chemie - Int. Ed. 52 (2013) 3953–3957. doi:10.1002/anie.201300519.[18] Q.-B. Hoang, V.-T. Mai, D.-K. Nguyen, D.Q. Truong, X.-D. Mai, Crosslinking induced photoluminescence quenching in polyvinyl alcohol-carbon quantum dot composite, Mater. Today Chem. 12 (2019) 166–172. doi:10.1016/j.mtchem.2019.01.003.

scholarly journals Quantum confinement-tunable intersystem crossing and the triplet state lifetime of cationic porphyrin–CdTe quantum dot nano-assemblies

2015 ◽  
Vol 51 (38) ◽  
pp. 8010-8013 ◽  
Author(s):  
Ghada H. Ahmed ◽  
Shawkat M. Aly ◽  
Anwar Usman ◽  
Mohamed S. Eita ◽  
Vasily A. Melnikov ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Dot ◽  
Triplet State ◽  
Quantum Confinement ◽  
Cdte Quantum Dots ◽  
Intersystem Crossing ◽  
Cationic Porphyrins ◽  
Cationic Porphyrin ◽  
Cdte Quantum Dot

We show the possibility of modulating the triplet-state lifetime of cationic porphyrins on the surface of CdTe quantum dots.

scholarly journals A novel pollen-tracking method: using quantum dots as pollen labels

2018 ◽  
Author(s):  
Corneile Minnaar ◽  
Bruce Anderson
Keyword(s):  
Quantum Dots ◽  
Oleic Acid ◽  
Quantum Dot ◽  
Uv Light ◽  
Semiconductor Nanocrystals ◽  
Bright Light ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Pollen Transport ◽  
History Of

ABSTRACTTo understand the evolution of flowers and mating systems in animal-pollinated plants, we have to directly address the function for which flowers evolved—the movement of pollen from anthers to stigmas. However, despite a long history of making significant advances in our understanding natural selection and evolution, the field of pollination biology has largely studied pollen movement indirectly (e.g., pollen analogues or paternity assignment to seeds) due to a lack of suitable pollen tracking methods. Here, we develop and test a novel pollen-tracking technique using quantum dots as pollen-grain labels. Quantum dots are semiconductor nanocrystals so small in size that they behave like artificial atoms. When exposed to UV light, they emit extremely bright light in a range of different colours. Their photostability, broad excitation range, and customisable binding-li-gands make quantum dots ideal bio-labels. We tested the suitability of CuInSexS2-x/ZnS (core/shell) quantum dots with oleic acid (zinc-oleate complex) ligands as pollen-grain labels. We found that quantum dots attach to pollen grains of four different species even after agitation in a polar solvent, suggesting that the oleic acid ligands on quantum dots bind to pollenkitt surrounding pollen grains. We also showed that most pollen grains within anthers of the same four species are labelled with quantum dots after applying sufficient quantum-dot solution to anthers. To test whether quantum-dot pollen-labels influenced pollen transport, we conducted pollen transfer trials on Sparaxis villosa (Iridaceae) using captively reared honeybees. We found no difference in pollen transport between labelled and unlabelled pollen grains. Our experiments therefore demonstrate the potential for quantum dots to be used as easily applied pollen labels, which allow subsequent tracking of the fates of pollen grains in the field. The ability to track pollen grain movement in situ, may finally allow us to address an historically neglected aspect of plant reproductive ecology and evolution.

Sign in / Sign up

Export Citation Format

Share Document