Carbon Dots: A New Type of Carbon-Based Nanomaterial with Wide Applications

ACS Central Science, Journal Year: 2020, Volume and Issue: 6(12), P. 2179 - 2195

Published: Dec. 14, 2020

Carbon dots (CDs), as a new type of carbon-based nanomaterial, have attracted broad research interest for years, because their diverse physicochemical properties and favorable attributes like good biocompatibility, unique optical properties, low cost, ecofriendliness, abundant functional groups (e.g., amino, hydroxyl, carboxyl), high stability, electron mobility. In this Outlook, we comprehensively summarize the classification CDs based on analysis formation mechanism, micro-/nanostructure property features, describe synthetic methods including strong absorption, photoluminescence, phosphorescence. Furthermore, recent significant advances in applications, (sensor, anticounterfeiting), energy (light-emitting diodes, catalysis, photovoltaics, supercapacitors), promising biomedicine, are systematically highlighted. Finally, envisage key issues to be challenged, future directions, perspectives show full picture CDs-based materials.

Language: Английский

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The light of carbon dots: From mechanism to applications

Matter, Journal Year: 2022, Volume and Issue: 5(1), P. 110 - 149

Published: Jan. 1, 2022

Language: Английский

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Recent advances in persistent luminescence based on molecular hybrid materials

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(9), P. 5564 - 5589

Published: Jan. 1, 2021

In this review, we summarize recent advances in establishing persistently luminescent materials from the view of examining experimental and theoretical approaches to room-temperature phosphorescence thermally-activated delayed fluorescence.

Language: Английский

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Time‐Dependent Phosphorescence Colors from Carbon Dots for Advanced Dynamic Information Encryption

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(16)

Published: March 12, 2021

Abstract The development of phosphorescent materials with time‐dependent phosphorescence colors (TDPCs) is considerable interest for application in advanced dynamic information encryption. In this study, TDPC realized carbon dots (CDs) synthesized by the one‐pot hydrothermal treatment levofloxacin. CD ink printed on paper (CD@paper) exhibits a change color from orange to green, 1 s after irradiation 395 nm light. However, when irradiated wavelengths shorter or longer than nm, CD@paper only green red phosphorescence, respectively. and originates low‐energy surface oxide triplet state high‐energy N‐related state, When suitable light energy (around wavelength), two centers can be simultaneously activated, emitting different decay rates. merge into an initially, exhibiting phenomenon. Based unusual properties CDs, kind multilevel, colored 3D code designed

Language: Английский

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Deciphering the catalytic mechanism of superoxide dismutase activity of carbon dot nanozyme

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Jan. 11, 2023

Nanozymes with superoxide dismutase (SOD)-like activity have attracted increasing interest due to their ability scavenge anion, the origin of most reactive oxygen species in vivo. However, SOD nanozymes reported thus far yet approach natural enzymes. Here, we report a carbon dot (C-dot) nanozyme catalytic over 10,000 U/mg, comparable that Through selected chemical modifications and theoretical calculations, show SOD-like C-dots relies on hydroxyl carboxyl groups for binding anions carbonyl conjugated π-system electron transfer. Moreover, C-dot exhibit intrinsic targeting oxidation-damaged cells effectively protect neuron ischemic stroke male mice model. Together, our study sheds light structure-activity relationship nanozymes, demonstrates potential treating oxidation stress related diseases.

Language: Английский

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Carbon‐Based Quantum Dots with Solid‐State Photoluminescent: Mechanism, Implementation, and Application

Small, Journal Year: 2020, Volume and Issue: 16(48)

Published: Nov. 3, 2020

Abstract Carbon‐based quantum dots (CQDs), including spherical carbon and graphene dots, are an emerging class of photoluminescent (PL) materials with unique properties. Great progress has been made in the design fabrication high‐performance CQDs, however, challenge developing solid‐state PL CQDs have aroused great interest among researchers. A clear mechanism is basis for development light emission also a prerequisite realization multiple practical applications. However, extremely complex structure CQD greatly limits understanding CQDs. So far, variety models proposed to explain but they not unified. This review summarizes current from perspective energy band theory electronic transitions. In addition, common strategies realizing summarized. Furthermore, applications fields light‐emitting devices, anti‐counterfeiting, fingerprint detection, etc., proposed. Finally, brief outlook given, highlighting problems, directions

Language: Английский

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Tailored Fabrication of Carbon Dot Composites with Full‐Color Ultralong Room‐Temperature Phosphorescence for Multidimensional Encryption

Advanced Science, Journal Year: 2021, Volume and Issue: 9(3)

Published: Nov. 19, 2021

Abstract Ultralong room‐temperature phosphorescence (RTP) is highly useful for information encryption, organic electronics, bioelectronics, etc. However, the preparation of related metal‐free materials with multiple colors across full spectrum remains a major challenge. Herein, facile method developed to fabricate boron‐doped carbon dot (B‐CD) composites full‐color long lifetime RTP continuously tailorable in range 466–638 nm simply by pyrolysis citric acid and boric precursors various mass ratios at different temperatures. This leads formation luminescent B‐CD centers rigid polycrystalline B 2 O 3 matrix, which effectively stabilizes triplet excited states B‐CDs. Thus, become phosphorescent over relatively period (5–12 s) after removal irradiation source. Meanwhile, increased particle size oxidation degree B‐CDs obtained larger feeding or higher temperature shift from blue red. Due luminescence centers, can also be finely modulated excitation wavelength. The resulting tunable further allow variety distinctive applications multidimensional encryption handily utilizing space, time, color variations.

Language: Английский

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Photo‐Stimulated Polychromatic Room Temperature Phosphorescence of Carbon Dots

Small, Journal Year: 2020, Volume and Issue: 16(31)

Published: June 29, 2020

Single-component multicolor luminescence, particularly phosphorescence materials are highly attractive both in numerous applications and in-depth understanding the light-emission processes, but formidable challenges still exist for preparing such materials. Herein, a very facile approach is reported to synthesize carbon dots (CDs) (named MP-CDs) that exhibit fluorescence (FL), more remarkably, long-lived room temperature (RTP) under ambient conditions. The FL RTP colors of CDs powder observed change from blue green cyan yellow, respectively, with excitation wavelength shifting 254 420 nm. Further studies demonstrate emissions can be attributed existence multiple emitting centers relatively higher reaction plays critical role achieving RTP. Given unique optical properties, preliminary application MP-CDs advanced anti-counterfeiting presented. This study not only proposes strategy prepare photo-stimulated materials, also reveals great potentials exploiting novel properties.

Language: Английский

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Aggregation and luminescence in carbonized polymer dots

Aggregate, Journal Year: 2022, Volume and Issue: 3(2)

Published: Jan. 20, 2022

Abstract The aggregate luminescence behavior of organic luminescent materials has been studied extensively. As a new kind nanomaterials, carbonized polymer dots (CPDs) not only inherit the stability and biocompatibility carbon materials, but also possess tunability, water solubility, high photoluminescence quantum yield rendering them strong candidate for next generation light‐emitting materials. Previously, people mainly understood its from perspective some mechanisms are still unclear. In this review, we discuss mechanism by referring to with emphasis on their aggregation behavior. Firstly, three representative phenomena briefly introduced. Chromophores present in CPDs elaborated further potential interactions between them, role crosslinked networks. On basis, special state summarized, relevant discussed detail consolidate statements.

Language: Английский

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Snapshots into carbon dots formation through a combined spectroscopic approach

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: May 11, 2021

The design of novel carbon dots with ad hoc properties requires a comprehensive understanding their formation mechanism, which is complex task considering the number variables involved, such as reaction time, structure precursors or synthetic protocol employed. Herein, we systematically investigated nanodots by tracking structural, chemical and photophysical features during hydrothermal synthesis. We demonstrate that consists 4 consecutive steps: (i) aggregation small organic molecules, (ii) dense core an extended shell, (iii) collapse shell (iv) aromatization core. In addition, provide examples routes towards tuning core-shell design, synthesizing five all consist electron-dense covered amine rich ligand shell.

Language: Английский

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