Light of carbon: Recent advancements of carbon dots for LEDs

Nano Energy, Год журнала: 2023, Номер 114, С. 108623 - 108623

Опубликована: Июнь 20, 2023

Язык: Английский

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Machine learning-guided realization of full-color high-quantum-yield carbon quantum dots

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Июнь 6, 2024

Abstract Carbon quantum dots (CQDs) have versatile applications in luminescence, whereas identifying optimal synthesis conditions has been challenging due to numerous parameters and multiple desired outcomes, creating an enormous search space. In this study, we present a novel multi-objective optimization strategy utilizing machine learning (ML) algorithm intelligently guide the hydrothermal of CQDs. Our closed-loop approach learns from limited sparse data, greatly reducing research cycle surpassing traditional trial-and-error methods. Moreover, it also reveals intricate links between target properties unifies objective function optimize like full-color photoluminescence (PL) wavelength high PL yields (PLQY). With only 63 experiments, achieve fluorescent CQDs with PLQY exceeding 60% across all colors. study represents significant advancement ML-guided synthesis, setting stage for developing new materials properties.

Язык: Английский

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Visible Light‐Activated Ultralong‐Lived Triplet Excitons of Carbon Dots for White‐Light Manipulated Anti‐Counterfeiting

Small, Год журнала: 2023, Номер 20(1)

Опубликована: Авг. 30, 2023

Abstract Room temperature phosphorescence (RTP) has emerged as an interesting but rare phenomenon with multiple potential applications in anti‐counterfeiting, optoelectronic devices, and biosensing. Nevertheless, the pursuit of ultralong lifetimes RTP under visible light excitation presents a significant challenge. Here, new phosphorescent materials that can be excited by record‐long are demonstrated, realized through embedding nitrogen doped carbon dots (N‐CDs) into poly(vinyl alcohol) (PVA) film. The lifetime N‐CDs@PVA film is remarkably extended to 2.1 s 420 nm, representing highest recorded value for light‐excited materials. Theoretical experimental studies reveal robust hydrogen bonding interactions effectively reduce non‐radiative decay rate radiative transition triplet excitons, thus dramatically prolong lifetime. Notably, emission also activated easily accessible low‐power white‐light‐emitting diode. More significantly, practical state‐of‐the‐art anti‐counterfeiting security optical information storage domains further demonstrated. This research offers exciting opportunities utilizing light‐activated ultralong‐lived systems wide range promising applications.

Язык: Английский

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Advances in Shell and Core Engineering of Carbonized Polymer Dots for Enhanced Applications

Accounts of Chemical Research, Год журнала: 2024, Номер 57(19), С. 2928 - 2939

Опубликована: Сен. 19, 2024

ConspectusCarbon dots (CDs), as a novel type of fluorescent nanocarbon material, attract widespread attention in nanomedicine, optoelectronic devices, and energy conversion/storage due to their excellent optical properties, low toxicity, high stability. They can be classified graphene quantum dots, carbon carbonized polymer (CPDs). Among these, CPDs exhibit tunable structures components that allow fine-tuning making them one the most popular types CDs recent years. However, structural complexity stimulates deep exploration relationship between unique structure luminescent performance. As an organic-inorganic hybrid system, diversity self-limited state cores polymer-hybrid shell layers makes understanding underlying mechanisms structure-property relationships very challenging task. In this context, elucidating composition factors affect properties is vital if enormous potential realized. Achieving controllable with predefined via adoption specific functionalization strategies prized goal current researchers field.In Account, we describe efforts made by our group synthesis, mechanism analysis, regulation, functional applications CPDs, particular emphasis on design core-shell tailored for fields optoelectronics energy. Specifically, through rational selection precursors, optimization reaction conditions, postmodification have demonstrated it possible regulate both core layers, thereby achieving full-spectrum emission, yield, persistent luminescence, thermally activated delayed fluorescence, laser action CPDs. Furthermore, established structure-performance proposed universal strategy synergistic interactions carbon-based surface micronanostructures. addition, unveiled luminescence cross-linked specifically "cross-linking synergistically inducing quantum-state luminescence", which addresses challenge efficient circularly polarized liquid solid phases Subsequently, strong cross-linking, dual-rigidity, ordering preparation methods were introduced, pioneering emission from blue near-infrared wavelengths. Additionally, developed new "confined composite nanocrystals CPDs", leading various high-performance hydrogen evolution catalysts water electrolysis. The not only possessed but also enabled efficiencies field conversion, thus maximizing utilization Finally, discuss important trends CPD research development. Overall, Account summarizes latest advancements years, providing case-studies enable structure-property-performance regulation guiding future expansion application

Язык: Английский

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Achieving Bright and Long‐Lived Aqueous Room‐Temperature Phosphorescence of Carbon Nitrogen Dots Through In Situ Host–Guest Binding

Advanced Materials, Год журнала: 2024, Номер 36(24)

Опубликована: Фев. 29, 2024

Abstract The development of bright and long‐lived aqueous room‐temperature phosphorescent (RTP) materials holds paramount importance in broadening the application scope RTP material system. However, conventional usually exhibit low efficiency short lifetime solution. Herein, an situ host–guest strategy is proposed to achieve cyanuric acid (CA)‐derived carbon nitrogen dots (CNDs) composite (CNDs@CA) that demonstrates a significant enhancement both quantum yield (QY) mediated by water. Detailed investigations reveal robust hydrogen bonding networks between CNDs@CA water effectively stabilize triplet excitons suppress nonradiative decays, as well facilitate efficient energy transfer from CA CNDs, thereby prolonging enhancing RTP. QY can be increased 26.89% (3.9‐fold increase) 951.25 ms (5.5‐fold increase), respectively, with incorporation 50 wt% under ambient conditions. Even fully environments (with up 400 added), exhibits persistent water‐boosted properties, demonstrating exceptional stability. property solutions presents potential for high signal‐to‐noise ratio afterglow bioimaging advanced information encryption.

Язык: Английский

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Fluorescent carbon quantum dots with controllable physicochemical properties fantastic for emerging applications: A review

Carbon Neutralization, Год журнала: 2024, Номер 3(2), С. 245 - 284

Опубликована: Март 1, 2024

Abstract Carbon quantum dots (CQDs) have emerged as prominent contenders in the realm of luminescent nanomaterials over past decade owing to their tunable optical properties, robust photostability, versatile surface functionalization and doping potential, low toxicity, straightforward synthesis utilizing environmentally friendly precursors. In this review, we commence with a concise introduction, presenting both top‐down bottom‐up strategies for eco‐friendly CQDs. Subsequently, delve into comprehensive examination CQDs' structure characteristics, encompassing ultraviolet–visible absorption confinement effects, state emissions contributing room‐temperature photoluminescence (PL). This review proceeds elucidate recent advancements modification CQDs, specifically focusing on oxidation, passivation, incorporation heteroatoms. These serve afford control physicochemical facilitating enhancement PL through decoration highly visible‐responsive is achieved by suppressing nonradiative recombination electron‐hole pairs, enabling red/blue shifts CQDs generation full‐color emission spectrum, regulating band‐gap states broaden photoabsorption range. Finally, offer an overview most developments applications fluorescent emphasizing utility biomedicine, sensors, lighting, displays, well photocatalysis.

Язык: Английский

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Onion-like multicolor thermally activated delayed fluorescent carbon quantum dots for efficient electroluminescent light-emitting diodes

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Апрель 8, 2024

Abstract Carbon quantum dots are emerging as promising nanomaterials for next-generation displays. The elaborate structural design is crucial achieving thermally activated delayed fluorescence, particularly improving external efficiency of electroluminescent light-emitting diodes. Here, we report the synthesis onion-like multicolor fluorescence carbon with yields 42.3–61.0%. Structural, spectroscopic characterization and computational studies reveal that structures assembled from monomer different sizes account decreased singlet-triplet energy gap, thereby efficient fluorescence. devices exhibit maximum luminances 3785–7550 cd m −2 6.0–9.9%. Importantly, owing to weak van der Waals interactions adequate solution processability, flexible a luminance 2554 realized. These findings facilitate development high-performance dots-based diodes practical applications.

Язык: Английский

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Long-lived dynamic room temperature phosphorescent carbon dots for advanced sensing and bioimaging applications

Coordination Chemistry Reviews, Год журнала: 2024, Номер 516, С. 215987 - 215987

Опубликована: Май 31, 2024

Язык: Английский

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Matrix-Free Thermally Activated Delayed Fluorescent Carbon Dots-Based Electroluminescent Light-Emitting Diodes Exceeding 5.6% External Quantum Efficiency

Nano Letters, Год журнала: 2024, Номер 24(9), С. 2904 - 2911

Опубликована: Фев. 22, 2024

Carbon dots (CDs) are promising luminescent emission layer materials for next generation electroluminescent light emitting diodes (EL-LEDs) due to their many advantages, such as environmental friendliness, low cost, and high stability. However, limited by the spin-forbidden properties of triplet transition, it is difficult improve external quantum efficiency (EQE) fluorescent CDs-based EL-LEDs. Meanwhile, traditional thermally activated delayed (TADF) CDs prepared using coating strategies utilize in EL-LEDs nonconductivity agent. Herein, we successfully developed matrix-free TADF with yellow achieved a device EQE 5.68%, which highest value reported In addition, also white an 1.70%. This study highlights importance interactions between precursors modulating electroluminescence emitters provides effective design principle CDs.

Язык: Английский

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Zero-dimensional nano-carbons: Synthesis, properties, and applications

Applied Physics Reviews, Год журнала: 2024, Номер 11(2)

Опубликована: Апрель 19, 2024

Zero-dimensional (0D) nano-carbons, including graphene quantum dots, nanodiamonds, and carbon represent the new generation of carbon-based nanomaterials with exceptional properties arising from diverse phenomena, such as surface, size, edge effects, which strongly depend on carbon–carbon bond configuration (sp2, sp3, a mixture sp2 sp3) particle size. Their unique physicochemical properties, optical, electronic, magnetic, reactivity, catalytic are valuable for energy conversion storage, sensing, catalysis, optoelectronic devices, modern nanotechnologies, biomedical, many other applications. This review aims to provide insights into distinctive effects 0D nano-carbon microstructures their that crucial cutting-edge fundamental studies broad range multifunctional The key synthesis methods different types nano-carbons current advances characterization computational techniques study structures structure–property relationships also discussed. concludes status, challenges, future opportunities in this rapidly developing research field.

Язык: Английский

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