OS1.3 - Optical Ozone Sensing by Composite Films of Noble Metals and CdSe/ZnS Quantum Dots

Blue luminescent carbon quantum dots (CQDs) were prepared from cyanobacteria by a hydrothermal method. The PL quantum yields of the obtained CQDs was 5.30%. Cyanobacteria-based carbon quantum dots/polyvinyl alcohol/nanocellulose composite films were prepared, which could emit bright blue under UV light. FTIR characterization showed that the composite films had hydroxyl groups on the surface and no new groups were formed after combining the three materials. The photoluminescence (PL) spectra revealed that the emission of the prepared CQDs was excitation dependent. Studies on the water resistance performance and light barrier properties of the composite films showed that they possessed higher water resistance properties and better UV/infrared light barrier properties. Therefore, we report the cyanobacteria-based carbon quantum dots/polyvinyl alcohol/nanocellulose composite films have the potential to be applied in flexible packaging materials, anti-fake materials, UV/infrared light barrier materials and so on.

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Nanobioconjugates for Signal Amplification in Electrochemical Biosensing

Molecules ◽

10.3390/molecules25153542 ◽

2020 ◽

Vol 25 (15) ◽

pp. 3542

Author(s):

Sebastian Cajigas ◽

Jahir Orozco

Keyword(s):

Quantum Dots ◽

Hybrid Materials ◽

Critical Review ◽

Signal Amplification ◽

Noble Metals ◽

Detection Limits ◽

Future Perspectives ◽

Electrochemical Biosensing ◽

Signal Response

Nanobioconjugates are hybrid materials that result from the coalescence of biomolecules and nanomaterials. They have emerged as a strategy to amplify the signal response in the biosensor field with the potential to enhance the sensitivity and detection limits of analytical assays. This critical review collects a myriad of strategies for the development of nanobioconjugates based on the conjugation of proteins, antibodies, carbohydrates, and DNA/RNA with noble metals, quantum dots, carbon- and magnetic-based nanomaterials, polymers, and complexes. It first discusses nanobioconjugates assembly and characterization to focus on the strategies to amplify a biorecognition event in biosensing, including molecular-, enzymatic-, and electroactive complex-based approaches. It provides some examples, current challenges, and future perspectives of nanobioconjugates for the amplification of signals in electrochemical biosensing.

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Perovskite Quantum Dots Embedded Composite Films Enhancing UV Response of Silicon Photodetectors for Broadband and Solar-Blind Light Detection

Advanced Optical Materials ◽

10.1002/adom.201800077 ◽

2018 ◽

Vol 6 (16) ◽

pp. 1800077 ◽

Cited By ~ 26

Author(s):

Mengjiao Zhang ◽

Lingxue Wang ◽

Linghai Meng ◽

Xian-Gang Wu ◽

Qinwen Tan ◽

...

Keyword(s):

Quantum Dots ◽

Composite Films ◽

Light Detection ◽

Solar Blind ◽

Perovskite Quantum Dots ◽

Uv Response

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Fluorescent and Mechanical Properties of Silicon Quantum Dots Modified Sodium Alginate-Carboxymethylcellulose Sodium Nanocomposite Bio-Polymer Films

Polymers ◽

10.3390/polym11091476 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1476 ◽

Cited By ~ 1

Author(s):

Ji ◽

Zhang ◽

Quan ◽

Huang ◽

...

Keyword(s):

Quantum Dots ◽

Sodium Alginate ◽

Polymer Films ◽

Composite Films ◽

Excitation Wavelength ◽

Hydrothermal Route ◽

Silicon Quantum Dots ◽

One Pot ◽

Bright Blue Fluorescence ◽

Bright Blue

Highly luminescent silicon quantum dots (SiQDs) were prepared via one-pot hydrothermal route. Furthermore, the optimal synthetic conditions, dependence of the emission spectrum on the excitation wavelength and fluorescent stability of SiQDs were investigated by fluorescence spectroscopy. SiQDs exhibited bright blue fluorescence, and photoluminescence (PL) lifetime is 10.8 ns when excited at 325 nm. The small-sized SiQDs (~3.3 nm) possessed uniform particle size, crystal lattice spacing of 0.31 nm and silicon (111), (220) crystal planes. Luminescent SiQDs/sodium alginate (SA)-carboxymethylcellulose sodium (CMC) nanocomposite bio-polymer films were successfully fabricated by incorporating SiQDs into the SA-CMC matrix. Meanwhile, SiQDs not only impart strong fluorescence to the polymer, but also make the composite films have favorable toughness.

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Air-exposing microwave-assisted synthesis of CuInS2/ZnS quantum dots for silicon solar cells with enhanced photovoltaic performance

RSC Advances ◽

10.1039/c5ra21454h ◽

2015 ◽

Vol 5 (124) ◽

pp. 102682-102688 ◽

Cited By ~ 12

Author(s):

Ming Hong ◽

Tongtong Xuan ◽

Jiaqing Liu ◽

Ziyao Jiang ◽

Yiwei Chen ◽

...

Keyword(s):

Quantum Dots ◽

Solar Cells ◽

Microwave Irradiation ◽

Conversion Efficiency ◽

Photovoltaic Performance ◽

Composite Films ◽

Silicon Solar Cells ◽

Microwave Assisted Synthesis ◽

Microwave Assisted ◽

Si Solar Cells

CIS/ZnS QDs were synthesized by microwave irradiation in air. The fabricated QDs/PMMA composite films were first applied to Si solar cells to improve the conversion efficiency by 3.8%.

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Third-Order Nonlinear Optical Properties of CdSe Quantum Dots and Ag Particles Composite Films

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2017.2324 ◽

2017 ◽

Vol 9 (4) ◽

pp. 515-519 ◽

Cited By ~ 2

Author(s):

Lili Wang ◽

Jinding Sun ◽

Shenchi Wan ◽

Jinan Lin ◽

Chengbao Yao ◽

...

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Nonlinear Optical ◽

Composite Films ◽

Nonlinear Optical Properties ◽

Cdse Quantum Dots ◽

Third Order ◽

Ag Particles

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Synthesis and Characterization of Polymeric Graphene Quantum Dots Based Nanocomposites for Humidity Sensing

Journal of Nanomaterials ◽

10.1155/2016/5849018 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Lam Minh Long ◽

Nguyen Nang Dinh ◽

Tran Quang Trung

Keyword(s):

Quantum Dots ◽

Atmospheric Pressure ◽

Graphene Quantum Dots ◽

Composite Films ◽

Fast Response ◽

Bulk Heterojunctions ◽

Humidity Sensing ◽

Best Value ◽

Doped Graphene

Graphene quantum dots (GQDs) were synthesized and incorporated with polyethylenedioxythiophene:poly(4-styrenesulfonate) (PEDOT:PSS) and carbon nanotube (CNT) to form a composite that can be used for humidity sensors. The 600 nm thick composite films contained bulk heterojunctions of CNT/GQD and CNT/PEDOT:PSS. The sensors made from the composites responded well to humidity in a range from 60 to 80% at room temperature and atmospheric pressure. With a CNT content of 0.4 wt.% (GPC-1) to 0.8 wt.% (GPC-2) and 1.2 wt.% (GPC-3), the sensitivity of the humidity sensing devices based on CNT-doped graphene quantum dot-PEDOT:PSS composites was increased from 4.5% (GPC-1) to 9.0% (GPC-1) and 11.0% (GPC-2), respectively. The fast response time of the GPC sensors was about 20 s and it was much improved due to CNTs doping in the composites. The best value of the recovery time was found to be of 40 s, for the GPC composite film doped with 1.2 wt.% CNT content.

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Characterization of Humidity Sensing of Polymeric Graphene-Quantum-Dots composites incorporated with silver nanowires

VNU Journal of Science Mathematics - Physics ◽

10.25073/2588-1124/vnumap.4216 ◽

2017 ◽

Vol 33 (3) ◽

Author(s):

Dinh Nguyen Nang ◽

Lam Minh Long ◽

Hoang Thi Thu ◽

Huynh Tri Phong ◽

Tran Quang Trung

Keyword(s):

Quantum Dots ◽

Relative Humidity ◽

Room Temperature ◽

Silver Nanowires ◽

Graphene Quantum Dots ◽

Composite Films ◽

Bulk Heterojunctions ◽

Humidity Sensing ◽

Best Value

Graphene quantum dots (GQDs) were synthesized and incorporated with polyethylenedioxythiophene:poly(4-styrenesulfonate) (PEDOT:PSS), Ag nanowires (AgNWs) to form a composite that can be used for enhancement of relative humidity (RH%) sensing. The composite films contained bulk heterojunctions of AgNW/GQD and AgNW/PEDOT:PSS. The sensors made from the composites responded well to relative humidity in a range from 10% to 50% at room temperature. With an AgNWs content ranging from 0.2 wt.% to 0.4 wt.% and 0.6 wt.%, the sensitivity of the relative humidity sensing devices based on AgNWs-doped GQDs+PEDOT:PSS composites was increased from 5.5% to 6.5 % and 15.2 %, respectively. The response time of the composite sensors was much improved due to AgNWs doping in the composites. For the 0.6 wt.% AgNWs-doped GQDs+PEDOT:PSS films, the best value of the recovery time was found to be of 30 s.

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