Optically Tunable Amino‐Functionalized Graphene Quantum Dots

Tetsuka, Hiroyuki; Asahi, Ryoji; Nagoya, Akira; Okamoto, Kazuo; Tajima, Ichiro; Ohta, Riichiro; Okamoto, Atsuto

doi:10.1002/adma.201201930

Cited by 769 publications

(630 citation statements)

References 23 publications

(34 reference statements)

Supporting

Mentioning

600

Contrasting

Unclassified

Order By: Relevance

“…155,156 Tetsuka and co-workers used the hydrothermal approach to treat graphene oxide sheets in ammonia 10 solution to get GQDs with a QY between ~19 -29%. 157 The emission of GQDs can be tuned by controlling the hydrothermal temperature (Figure 15(a)), and the QYs can be further enhanced to ~46% after modification with PEG. Wu et al used a one-step pyrolysis of a natural amino acid (i.e.…”

Section: Fluorescent Graphene Quantum Dotsmentioning

confidence: 99%

Ultra-small fluorescent inorganic nanoparticles for bioimaging

et al. 2014

View full text Add to dashboard Cite

show abstract

Section: Fluorescent Graphene Quantum Dotsmentioning

confidence: 99%

Ultra-small fluorescent inorganic nanoparticles for bioimaging

et al. 2014

View full text Add to dashboard Cite

show abstract

“…11 In addition, they may also have structural variety that can be determined using spectroscopic techniques such as Raman spectroscopy, in which significant differences can be found between amorphous C-dots 12 and GQDs. 13 Photoluminescent GQDs and C-dots are touted for their properties, such as small sizes, intrinsic and stable photoluminescence, biocompatibility, and ease of surface derivitization 11 while showing promise for applications such as chromatographic stationary phases, 14 drug-delivery vehicles, 15 photothermal therapies, 16 photocatalysis, 17 bioimaging, 4 and chemical sensing. 18 Graphene oxide nanosheets are also cited for use in similar applications, including intracellular drug delivery and cellular imaging; 19 in addition, graphene oxide can be chemically converted to graphene, 20 which has a host of exciting applications and fascinating properties that have been at the center of research and innovation in recent years.…”

Section: Introductionmentioning

confidence: 99%

Spectroscopic Characteristics of Carbon Dots (C-Dots) Derived from Carbon Fibers and Conversion to Sulfur-Bridged C-Dots Nanosheets

et al. 2015

View full text Add to dashboard Cite

We synthesized sub-10 nm carbon nanoparticles (CNPs) consistent with photoluminescent carbon dots (C-dots) from carbon fiber starting material. The production of different C-dots fractions was monitored over seven days. During the course of the reaction, one fraction of C-dots species with relatively high photoluminescence was short-lived, emerging during the first hour of reaction but disappearing after one day of reaction. Isolation of this species during the first hour of the reaction was crucial to obtaining higherluminescent C-dots species. When the reaction proceeded for one week, the appearance of larger nanostructures was observed over time, with lateral dimensions approaching 200 nm. The experimental evidence suggests that these larger species are formed from small C-dot nanoparticles bridged together by sulfur-based moieties between the C-dot edge groups, as if the C-dots polymerized by cross-linking the edge groups through sulfur bridges. Their size can be tailored by controlling the reaction time. Our results highlight the variety of CNP products, from sub-10 nm C-dots to $200 nm sulfur-containing carbon nanostructures, that can be produced over time during the oxidation reaction of the graphenic starting material. Our work provides a clear understanding of when to stop the oxidation reaction during the top-down production of Cdots to obtain highly photoluminescent species or a target average particle size.

show abstract

“…8,12,23 In spite of the controversial mechanism of CDs' photoluminescence (PL), it is widely accepted that surface groups can introduce trap states with different energy levels, which leads to the excitation-dependent emission. 22,24 The origin of NCDs' tunable fluorescence has been investigated by adjusting surface states, [25][26][27] and diverse fluorescence phenomena have been observed for NCDs prepared by various reactant precursors. For instance, Xu et al 28 developed a green heterogeneous synthetic method for NCDs with yellowish-green fluorescence.…”

mentioning

confidence: 99%

Fluorescently tuned nitrogen-doped carbon dots from carbon source with different content of carboxyl groups

et al. 2015

View full text Add to dashboard Cite

In this study, fluorescent nitrogen-doped carbon dots (NCDs) were tuned via varying the sources with different number of carboxyl groups. Owing to the interaction between amino and carboxyl, more amino groups conjugate the surface of the NCDs by the source with more carboxyl groups. Fluorescent NCDs were tuned via varying the sources with different content of carboxyl groups. Correspondingly, the nitrogen content, fluorescence quantum yields and lifetime of NCDs increases with the content of carboxyl groups from the source. Furthermore, cytotoxicity assay and cell imaging test indicate that the resultant NCDs possess low cytotoxicity and excellent biocompatibility.

show abstract

Optically Tunable Amino‐Functionalized Graphene Quantum Dots

Cited by 769 publications

References 23 publications

Ultra-small fluorescent inorganic nanoparticles for bioimaging

Ultra-small fluorescent inorganic nanoparticles for bioimaging

Spectroscopic Characteristics of Carbon Dots (C-Dots) Derived from Carbon Fibers and Conversion to Sulfur-Bridged C-Dots Nanosheets

Fluorescently tuned nitrogen-doped carbon dots from carbon source with different content of carboxyl groups

Contact Info

Product

Resources

About