Synthesis and characterization of Mono-disperse Carbon Quantum Dots from Fennel Seeds: Photoluminescence analysis using Machine Learning

Dager, Akansha; Uchida, Takashi; Maekawa, Toru; Tachibana, Masaru

doi:10.1038/s41598-019-50397-5

Cited by 289 publications

(170 citation statements)

References 51 publications

(116 reference statements)

Supporting

Mentioning

151

Contrasting

Order By: Relevance

“…The bands at 1,700 and 1,600 cm −1 were attributed to the vibrational absorption bands of −COOH and C=C, respectively. All FTIR peak assignments agree well with those previously reported studies for CQDs prepared differently (Vinci et al, 2015 ; Zhang et al, 2017 ; Dager et al, 2019 ). No obvious functional group differences between CQDs are demonstrated in Figure 2 , which suggests synthesis mechanism is similar, if not the same, between all samples.…”

Section: Resultssupporting

confidence: 90%

Efficient White Electrochemiluminescent Emission From Carbon Quantum Dot Films

et al. 2020

View full text Add to dashboard Cite

Carbon quantum dots (CQDs) were manufactured from citric acid and urea in a gram-scale synthesis with a controlled size range between 1. 5 and 23.8 nm. The size control was realized by varying volume of the precursor solution in a hydrothermal synthesis method. The prepared CQDs were investigated using electrochemiluminescence (ECL) spectroscopy at interfaces of their electrode films and electrolyte solution containing coreactants rather than conventional optoelectronic tests, providing an in-depth analysis of light-emission mechanisms of the so-called half-cells. ECL from the CQD films with TPrA and K 2 S 2 O 8 as coreactants provided information on the stability of the CQD radicals in the films. It was discovered that CQD •− has a powerful electron donating nature to sulfate radical to generate ECL at a relative efficiency of 96% to the Ru(bpy) 3 Cl 2 /K 2 S 2 O 8 coreactant system, indicating a strong performance in light emitting applications. The smaller the CQD particle sizes, the higher the ECL efficiency of the film interface, most likely due to the increased presence of surface states per mass of CQDs. Spooling ECL spectroscopy of the system revealed a potential-dependent light emission starting from a deep red color to blue-shifted intensity maximum, cool bright white emission with a correlated color temperature of 3,200 K. This color temperature is appropriate for most indoor lighting applications. The above ECL results provide information on the performance of CQD light emitters in films, permitting preliminary screening for light emitting candidates in optoelectronic applications. This screening has revealed CQD films as a powerful and cost-effective light emitting layer toward lighting devices for indoor applications.

show abstract

Section: Resultssupporting

confidence: 90%

Efficient White Electrochemiluminescent Emission From Carbon Quantum Dot Films

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Thus C-QDs often have an amorphous structure and poor photostability. Recently, our group reported the synthesis of excitation independent C-QDs; however, the synthesis process was time and energy-consuming 18 . Despite recent advancements in the synthesis technologies, developing a cost-effective, nonetheless rapid, and energy-efficient process remains a challenge to synthesize graphitized-C-QDs.…”

mentioning

confidence: 99%

Ultrafast synthesis of carbon quantum dots from fenugreek seeds using microwave plasma enhanced decomposition: application of C-QDs to grow fluorescent protein crystals

Dager

Baliyan

Kurosu

et al. 2020

Sci Rep

Self Cite

View full text Add to dashboard Cite

Herein, we present the rapid synthesis of mono-dispersed carbon quantum dots (c-QDs) via a singlestep microwave plasma-enhanced decomposition (MpeD) process. Highly-crystalline c-QDs were synthesized in a matter of 5 min using the fenugreek seeds as a sustainable carbon source. It is the first report, to the best of our knowledge, where c-QDs were synthesized using MpeD via natural carbon precursor. Synthesis of c-QDs requires no external temperature other than hydrogen (H 2) plasma. plasma containing the high-energy electrons and activated hydrogen ions predominantly provide the required energy directly into the reaction volume, thus maximizing the atom economy. c-QDs shows excellent photoluminescence (pL) activity along with the dual-mode of excitation-dependent pL emission (blue and redshift). We investigate the reason behind the dual-mode of excitation-dependent PL. To prove the efficacy of the MPED process, C-QDs were also derived from fenugreek seeds using the traditional synthesis process, highlighting their respective size-distribution, crystallinity, quantum yield, and PL. Notably, C-QDs synthesis via MPED was 97.2% faster than the traditional thermal decomposition process. to the best of our knowledge, the present methodology to synthesize c-QDs via natural source employing MPED is three times faster and far more energy-efficient than reported so far. Additionally, the application of C-QDs to produce the florescent lysozyme protein crystals "hybrid bio-nano crystals" is also discussed. Such a guest-host strategy can be exploited to develop diverse and complex "bio-nano systems". The florescent lysozyme protein crystals could provide a platform for the development of novel next-generation polychrome luminescent crystals. Recently, carbon quantum dots (C-QDs) have gained much attention due to the unique characteristics, notably, alluring fluorescence, chemical-stability, water-solubility, and magnificent photostability properties. C-QDs, owning such properties, have found numerous applications in optoelectronics, bio-imaging, energy-harvesting, and ingenious sensing. Predominantly, C-QDs synthesis is broadly classified into "top-down" and "bottom-up" approaches 1,2. In the top-down approach, C-QDs are synthesized via employing the arc discharge, laser ablation, and chemical oxidation techniques that essentially disintegrate the large graphitic carbon materials into smaller ones 3-5. Alternatively, in the bottom-up approach, C-QDs are synthesized what is known as chemical synthesis such as; the thermal decomposition 6 , hydrothermal 7 , electrochemical oxidation 8 , and microwave pyrolysis 9-12. The majority of the synthesis processes are usually energy consuming, pretty cumbersome, and demand expensive carbon sources that are often toxic 12-16. Concerning C-QDs synthesis, conventional methods such as thermal

show abstract

“…Synthesis of mono-dispersed carbon quantum dots via a single-step thermal decomposition method was reported using the fennel seeds (Foeniculum vulgare) ( Fig. 3) (Dager et al 2019); the prepared quantum dots showed significant colloidal, photostability, environmental stability (pH), and did not need extra surface passivation step for improving their fluorescence. Additionally, these particles demonstrated remarkable photoluminescence activity and excitation-independent emission.…”

Section: Eco-friendly and Sustainable Synthesis Of Carbon Quantum Dotsmentioning

confidence: 99%

“…Additionally, these particles demonstrated remarkable photoluminescence activity and excitation-independent emission. The effect of some factors like reaction time and temperature on pyrolysis provided insight into the formation of carbon quantum dots; these quantum dots can be applied in biosensing, cellular imaging, lightemitting diode, solar cell, supercapacitor, printing, and sensors (Dager et al 2019).…”

Section: Eco-friendly and Sustainable Synthesis Of Carbon Quantum Dotsmentioning

confidence: 99%

“…The functionalization of graphene quantum dots with peptides or antibodies for imaging with high cancers targeting issues should be additionally investigated. The optimization of emission characteristics and multi-photon excitations of graphene quantum dots, their innovative neurobehavioral analyses applications, the brain gene therapy, and brain barrier penetration through blood capillaries, should be scrutinized (Dager et al 2019;Sharma and Das 2019;Wang et al 2014a;Namdari et al 2017). The side effects, which possibly can be detected by applying graphene quantum dots, need to be evaluated.…”

Section: Imaging and Bioimagingmentioning

confidence: 99%

See 1 more Smart Citation

Green synthesis, biomedical and biotechnological applications of carbon and graphene quantum dots. A review

2020

View full text Add to dashboard Cite

Carbon and graphene quantum dots are prepared using top-down and bottom-up methods. Sustainable synthesis of quantum dots has several advantages such as the use of low-cost and non-toxic raw materials, simple operations, expeditious reactions, renewable resources and straightforward post-processing steps. These nanomaterials are promising for clinical and biomedical sciences, especially in bioimaging, diagnosis, bioanalytical assays and biosensors. Here we review green methods for the fabrication of quantum dots, and biomedical and biotechnological applications.

show abstract

Synthesis and characterization of Mono-disperse Carbon Quantum Dots from Fennel Seeds: Photoluminescence analysis using Machine Learning

Cited by 289 publications

References 51 publications

Efficient White Electrochemiluminescent Emission From Carbon Quantum Dot Films

Efficient White Electrochemiluminescent Emission From Carbon Quantum Dot Films

Ultrafast synthesis of carbon quantum dots from fenugreek seeds using microwave plasma enhanced decomposition: application of C-QDs to grow fluorescent protein crystals

Green synthesis, biomedical and biotechnological applications of carbon and graphene quantum dots. A review

Contact Info

Product

Resources

About