Customized Carbon Dots with Predictable Optical Properties Synthesized at Room Temperature Guided by Machine Learning

: The prevention and treatment of various infections caused by microbes through antibiotics are becoming less effective due to antimicrobial resistance. Researches are focused on antimicrobial nanomaterials to inhibit bacterial growth and destroy the cells, to replace conventional antibiotics. Recently, carbon dots (C-Dots) become attractive candidates for a wide range of applications, including the detection and treatment of pathogens. In addition to low toxicity, ease of synthesis and functionalization, and high biocompatibility, C-Dots show excellent optical properties such as multi-emission, high brightness, and photostability. C-Dots have shown great potential in various fields, such as biosensing, nanomedicine, photo-catalysis, and bioimaging. This review focuses on the origin and synthesis of various C-Dots with special emphasis on bacterial detection, the antibacterial effect of CDots, and their mechanism.

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Polymorphic gallium for active resonance tuning in photonic nanostructures: from bulk gallium to two-dimensional (2D) gallenene

Nanophotonics ◽

10.1515/nanoph-2020-0314 ◽

2020 ◽

Vol 9 (14) ◽

pp. 4233-4252

Author(s):

Yael Gutiérrez ◽

Pablo García-Fernández ◽

Javier Junquera ◽

April S. Brown ◽

Fernando Moreno ◽

...

Keyword(s):

Optical Properties ◽

Room Temperature ◽

Phase Change Materials ◽

Two Dimensional ◽

Active Materials ◽

Promising Candidate ◽

Plasmonic Structures ◽

Resonance Tuning ◽

The Many ◽

Optical Behavior

AbstractReconfigurable plasmonics is driving an extensive quest for active materials that can support a controllable modulation of their optical properties for dynamically tunable plasmonic structures. Here, polymorphic gallium (Ga) is demonstrated to be a very promising candidate for adaptive plasmonics and reconfigurable photonics applications. The Ga sp-metal is widely known as a liquid metal at room temperature. In addition to the many other compelling attributes of nanostructured Ga, including minimal oxidation and biocompatibility, its six phases have varying degrees of metallic character, providing a wide gamut of electrical conductivity and optical behavior tunability. Here, the dielectric function of the several Ga phases is introduced and correlated with their respective electronic structures. The key conditions for optimal optical modulation and switching for each Ga phase are evaluated. Additionally, we provide a comparison of Ga with other more common phase-change materials, showing better performance of Ga at optical frequencies. Furthermore, we first report, to the best of our knowledge, the optical properties of liquid Ga in the terahertz (THz) range showing its broad plasmonic tunability from ultraviolet to visible-infrared and down to the THz regime. Finally, we provide both computational and experimental evidence of extension of Ga polymorphism to bidimensional two-dimensional (2D) gallenene, paving the way to new bidimensional reconfigurable plasmonic platforms.

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Near‐Infrared‐Excited Multicolor Afterglow in Carbon Dots‐Based Room‐Temperature Afterglow Materials

Angewandte Chemie International Edition ◽

10.1002/anie.202108696 ◽

2021 ◽

Author(s):

Yihao Zheng ◽

Haopeng Wei ◽

Ping Liang ◽

Xiaokai Xu ◽

Xingcai Zhang ◽

...

Keyword(s):

Carbon Dots ◽

Room Temperature ◽

Near Infrared

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Tuning Optical Properties of Nitrogen-Doped Carbon Dots Through Fluorescence Resonance Energy Transfer Using Rhodamine B for Ratiometric Sensing of Mercury ion

Analytical Methods ◽

10.1039/d1ay00068c ◽

2021 ◽

Author(s):

Alagan Muthurasu ◽

V GANESH

Keyword(s):

Optical Properties ◽

Energy Transfer ◽

Rhodamine B ◽

Carbon Dots ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Nitrogen Doped ◽

Physical Chemical ◽

Doped Carbon Dots ◽

Nitrogen Doped Carbon

Carbon dots (CDs) exhibiting fluorescence property are generally derived from carbonaceous materials and possessing ultra small size with various exciting physical, chemical and photo-properties that have been used in many...

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A Facile Co-crystallization Approach to Fabricate Two-component Carbon Dots Composites Showing Time-Dependent Evolutive Room Temperature Phosphorescence Colors

Nanoscale Advances ◽

10.1039/d1na00362c ◽

2021 ◽

Author(s):

Jian Qu ◽

Xin Zhang ◽

Zhong-Jie Wang ◽

Shuyan Zhang ◽

Yejian Yu ◽

...

Keyword(s):

Carbon Dots ◽

Room Temperature ◽

Data Encryption ◽

Time Dependent ◽

Security Level ◽

Room Temperature Phosphorescence ◽

Two Component ◽

Carbon Based

Time-dependent evolutive afterglow materials can increase the security level by providing additional encryption modes in anti-counterfeiting and data encryption. The design of carbon-based materials with dynamic afterglow colors is attractive...

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Formation Mechanism and Chirality Evolution of Chiral Carbon Dots Prepared via Radical Assisted Synthesis at Room Temperature

Nanoscale ◽

10.1039/d1nr01927a ◽

2021 ◽

Author(s):

Lorenzo Branzi ◽

Giacomo Lucchini ◽

Elti Cattaruzza ◽

Nicola Pinna ◽

Alvise Benedetti ◽

...

Keyword(s):

Thermal Treatment ◽

Formation Mechanism ◽

Carbon Dots ◽

Room Temperature ◽

Chiral Carbon

We report on a Cu(II) catalyzed process for the production of cysteine based chiral carbon dots, the process does not require any thermal treatment and the carbon dots formation is...

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Two-step machine learning enables optimized nanoparticle synthesis

npj Computational Materials ◽

10.1038/s41524-021-00520-w ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Flore Mekki-Berrada ◽

Zekun Ren ◽

Tan Huang ◽

Wai Kuan Wong ◽

Fang Zheng ◽

...

Keyword(s):

Machine Learning ◽

Optical Properties ◽

Materials Science ◽

Nanoparticle Synthesis ◽

Bayesian Optimization ◽

Absorbance Spectrum ◽

Nanomaterial Synthesis ◽

Target Spectrum ◽

Colour Palette ◽

Algorithmic Framework

AbstractIn materials science, the discovery of recipes that yield nanomaterials with defined optical properties is costly and time-consuming. In this study, we present a two-step framework for a machine learning-driven high-throughput microfluidic platform to rapidly produce silver nanoparticles with the desired absorbance spectrum. Combining a Gaussian process-based Bayesian optimization (BO) with a deep neural network (DNN), the algorithmic framework is able to converge towards the target spectrum after sampling 120 conditions. Once the dataset is large enough to train the DNN with sufficient accuracy in the region of the target spectrum, the DNN is used to predict the colour palette accessible with the reaction synthesis. While remaining interpretable by humans, the proposed framework efficiently optimizes the nanomaterial synthesis and can extract fundamental knowledge of the relationship between chemical composition and optical properties, such as the role of each reactant on the shape and amplitude of the absorbance spectrum.

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Role of non-magnetic dopants on the room temperature ferromagnetism and optical properties of BaSnO3 perovskite

Journal of Solid State Chemistry ◽

10.1016/j.jssc.2019.121028 ◽

2020 ◽

Vol 281 ◽

pp. 121028 ◽

Cited By ~ 5

Author(s):

Saad Mabrouk Yakout ◽

Hanan A. Mousa ◽

Hala T. Handal ◽

Walid Sharmoukh

Keyword(s):

Optical Properties ◽

Room Temperature ◽

Room Temperature Ferromagnetism

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Electrical and Optical Properties of Si+ and P+ Implanted InP:Fe

MRS Proceedings ◽

10.1557/proc-201-325 ◽

1990 ◽

Vol 201 ◽

Author(s):

Honglie Shen ◽

Genqing Yang ◽

Zuyao Zhou ◽

Guanqun Xia ◽

Shichang Zou

Keyword(s):

Optical Properties ◽

Silicon Nitride ◽

Temperature Dependence ◽

Optimal Condition ◽

Room Temperature ◽

Broad Band ◽

Photoluminescence Spectra ◽

Electrical And Optical Properties ◽

Spectrum Measurement ◽

Single Implant

AbstractDual implantations of Si+ and P+ into InP:Fe were performed both at 200°C and room temperature. Si+ ions were implanted by 150keV with doses ranging from 5×1013 /cm2 to 1×1015 /cm2, while P+ ions were implanted by 110keV. 160keV and 180keV with doses ranging from 1×l013 /cm2 to 1×1015 /cm2. Hall measurements and photoluminescence spectra were used to characterize the silicon nitride encapsulated annealed samples. It was found that enhanced activation can be obtained by Si+ and P+ dual implantations. The optimal condition for dual implantations is that the atomic distribution of implanted P overlaps that of implanted si with the same implant dose. For a dose of 5×l014 /cm2, the highest activation for dual implants is 70% while the activation for single implant is 40% after annealing at 750°C for 15 minutes. PL spectrum measurement was carried out at temperatures from 11K to 100K. A broad band at about 1.26eV was found in Si+ implanted samples, of which the intensity increased with increasing of the Si dose and decreased with increasing of the co-implant P+ dose. The temperature dependence of the broad band showed that it is a complex (Vp-Sip) related band. All these results indicate that silicon is an amphoteric species in InP.

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