Ratiometric sensing of metabolites using dual-emitting ZnS:Mn 2+ quantum dots as sole luminophore via surface chemistry design

The preparation and surface chemistry Si quantum dots (SiQDs) are currently an intense focus of research because of their size dependent optical properties and many potential applications. SiQDs offer several advantages over other quantum dots; Si is earth abundant, non-toxic and biocompatible. This account briefly highlights recent advancements made by our research group related to the synthesis, functionalization, surface dependent optical properties and applications of SiQDs.

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Persistent DNA methylation changes in zebrafish following graphene quantum dots exposure in surface chemistry-dependent manner

Ecotoxicology and Environmental Safety ◽

10.1016/j.ecoenv.2018.11.053 ◽

2019 ◽

Vol 169 ◽

pp. 370-375 ◽

Cited By ~ 8

Author(s):

Junjie Hu ◽

Wenting Lin ◽

Boji Lin ◽

Kangming Wu ◽

Hongbo Fan ◽

...

Keyword(s):

Dna Methylation ◽

Quantum Dots ◽

Surface Chemistry ◽

Graphene Quantum Dots ◽

Dependent Manner

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Surface chemistry and density distribution influence on visible luminescence of silicon quantum dots: an experimental and theoretical approach

Physical Chemistry Chemical Physics ◽

10.1039/c6cp07398k ◽

2017 ◽

Vol 19 (2) ◽

pp. 1526-1535 ◽

Cited By ~ 5

Author(s):

Ateet Dutt ◽

Yasuhiro Matsumoto ◽

G. Santana-Rodríguez ◽

Estrella Ramos ◽

B. Marel Monroy ◽

...

Keyword(s):

Quantum Dots ◽

Surface Chemistry ◽

Density Distribution ◽

Theoretical Approach ◽

Silicon Quantum Dots ◽

Visible Luminescence

Visible luminescence and hence the mechanism of emission from Si QDs depending on the size and/or the passivation environment are presented.

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Ligand-Length Modification in CsPbBr3 Perovskite Nanocrystals and Bilayers with PbS Quantum Dots for Improved Photodetection Performance

Nanomaterials ◽

10.3390/nano10071297 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1297 ◽

Cited By ~ 1

Author(s):

Juan Navarro Arenas ◽

Ananthakumar Soosaimanickam ◽

Hamid Pashaei Adl ◽

Rafael Abargues ◽

Pablo P. Boix ◽

...

Keyword(s):

Quantum Dots ◽

Surface Chemistry ◽

Optical Sensors ◽

Ligand Exchange ◽

Near Infrared ◽

Future Internet ◽

Single Step ◽

Perovskite Nanocrystals ◽

Internet Of Things Technology ◽

Pbs Quantum Dots

Nanocrystals surface chemistry engineering offers a direct approach to tune charge carrier dynamics in nanocrystals-based photodetectors. For this purpose, we have investigated the effects of altering the surface chemistry of thin films of CsPbBr3 perovskite nanocrystals produced by the doctor blading technique, via solid state ligand-exchange using 3-mercaptopropionic acid (MPA). The electrical and electro-optical properties of photovoltaic and photoconductor devices were improved after the MPA ligand exchange, mainly because of a mobility increase up to 5 × 10−3 cm 2 / Vs . The same technology was developed to build a tandem photovoltaic device based on a bilayer of PbS quantum dots (QDs) and CsPbBr3 perovskite nanocrystals. Here, the ligand exchange was successfully carried out in a single step after the deposition of these two layers. The photodetector device showed responsivities around 40 and 20 mA/W at visible and near infrared wavelengths, respectively. This strategy can be of interest for future visible-NIR cameras, optical sensors, or receivers in photonic devices for future Internet-of-Things technology.

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Size-Dependent Antibacterial Behavior of Graphene Quantum Dots

Volume 15: Safety, Reliability and Risk; Virtual Podium (Posters) ◽

10.1115/imece2013-64872 ◽

2013 ◽

Cited By ~ 1

Author(s):

Siheng Su ◽

Carla B. Shelton ◽

Jingjing Qiu

Keyword(s):

Quantum Dots ◽

Surface Chemistry ◽

Graphene Quantum Dots ◽

Gel Filtration ◽

Filtration Method ◽

E Coli ◽

Size Dependent ◽

Mtt Method ◽

Diphenyltetrazolium Bromide ◽

Standard Plate

In this study, the antibacterial behavior of differing sized graphene quantum dots (GQDs) was studied. The gram negative bacteria, Escherichia coli (E. coli), were used as the bacteria mode. Different sized GQDs with tunable fluorescent colors were acquired by a gel-filtration method. The size, surface chemistry, and photoluminescence properties of GQDs were characterized, respectively. The viability of GQDs treated bacteria was determined by the standard plate counting method. Moreover, the reactive oxidative species (ROS) level was detected by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) method. The integrality of the bacteria membrane was observed under the scanning electron microscopy (SEM). The experimental results indicated that GQDs demonstrated size-dependent and surface chemistry-dependent antibacterial behaviors. This research provided insightful guidelines in the selection of suitable GQDs for their potential bioapplications.

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Cascade surface modification of colloidal quantum dot inks enables efficient bulk homojunction photovoltaics

Nature Communications ◽

10.1038/s41467-019-13437-2 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 37

Author(s):

Min-Jae Choi ◽

F. Pelayo García de Arquer ◽

Andrew H. Proppe ◽

Ali Seifitokaldani ◽

Jongmin Choi ◽

...

Keyword(s):

Quantum Dots ◽

Surface Modification ◽

Surface Chemistry ◽

Surface Passivation ◽

Diffusion Length ◽

Power Conversion ◽

Colloidal Quantum Dots ◽

Semiconductor Materials ◽

Colloidal Quantum Dot ◽

Reduced Surface

AbstractControl over carrier type and doping levels in semiconductor materials is key for optoelectronic applications. In colloidal quantum dots (CQDs), these properties can be tuned by surface chemistry modification, but this has so far been accomplished at the expense of reduced surface passivation and compromised colloidal solubility; this has precluded the realization of advanced architectures such as CQD bulk homojunction solids. Here we introduce a cascade surface modification scheme that overcomes these limitations. This strategy provides control over doping and solubility and enables n-type and p-type CQD inks that are fully miscible in the same solvent with complete surface passivation. This enables the realization of homogeneous CQD bulk homojunction films that exhibit a 1.5 times increase in carrier diffusion length compared with the previous best CQD films. As a result, we demonstrate the highest power conversion efficiency (13.3%) reported among CQD solar cells.

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