One-pot pyrolysis preparation of carbon dots as eco-friendly nanoadditives of water-based lubricants

Ionic liquid modified carbon dots (CDs-IL) were successfully synthesized by one-pot pyrolysis. The tribological properties of CDs-IL as a kind of water-based lubricant additive were investigated under four-ball mode. The experimental results demonstrated that the added CDs-IL not only increased load-carrying capacity of base liquid but also displayed remarkable friction-reducing and antiwear properties. At an optimal concentration of 0.05[Formula: see text]wt.% and a proper load of 50[Formula: see text]N, the mean friction coefficient and wear volume reduced by 65% and 60%, respectively. The remarkable lubricating effect of CDs-IL was attributed to the boundary tribofilm formed by absorption and deposition of CDs-IL on rubbing surfaces. The lubricating effect of CDs-IL especially antiwear effect greatly attenuated when the load was lower or higher than 50 N because the function of deposition tribofilm formed by CDs-IL was suppressed by the absorption tribofilm or tribochemical film derived from triethanolamine in base liquid, respectively.

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One-pot synthesis of CeO2-carbon dots with enhanced peroxidase-like activity and carbon dots for ratiometric fluorescence detection of H2O2 and cholesterol

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2020.158323 ◽

2021 ◽

Vol 862 ◽

pp. 158323

Author(s):

Zhouping Yang ◽

Yang Liu ◽

Changfang Lu ◽

Guizhou Yue ◽

Yanying Wang ◽

...

Keyword(s):

Fluorescence Detection ◽

Carbon Dots ◽

Ratiometric Fluorescence ◽

One Pot ◽

One Pot Synthesis

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Facile Hydrothermal and Solvothermal Synthesis and Characterization of Nitrogen-Doped Carbon Dots from Palm Kernel Shell Precursor

Applied Sciences ◽

10.3390/app11041630 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1630

Author(s):

Yakubu Newman Monday ◽

Jaafar Abdullah ◽

Nor Azah Yusof ◽

Suraya Abdul Rashid ◽

Rafidah Hanim Shueb

Keyword(s):

Carbon Dots ◽

Batch Reactor ◽

Average Particle Size ◽

Research Work ◽

Palm Kernel ◽

Average Particle ◽

One Pot ◽

Palm Kernel Shell ◽

Doped Carbon Dots ◽

Nitrogen Doped Carbon

Carbon dots (CDs), a nanomaterial synthesized from organic precursors rich in carbon content with excellent fluorescent property, are in high demand for many purposes, including sensing and biosensing applications. This research focused on preparing CDs from natural and abundant waste, palm kernel shells (PKS) obtained from palm oil biomass, aiming for sensing and biosensing applications. Ethylenediamine and L-phenylalanine doped CDs were produced via the hydrothermal and solvothermal methods using one-pot synthesis techniques in an autoclave batch reactor. The as-prepared N-CDs shows excellent photoluminescence (PL) property and a quantum yield (QY) of 13.7% for ethylenediamine (EDA) doped N-CDs (CDs-EDA) and 8.6% for L-phenylalanine (L-Ph) doped N-CDs (CDs-LPh) with an excitation/emission wavelength of 360 nm/450 nm. The transmission electron microscopy (TEM) images show the N-CDs have an average particle size of 2 nm for both CDs. UV-Visible spectrophotometric results showed C=C and C=O transition. FTIR results show and confirm the presence of functional groups, such as -OH, -C=O, -NH2 on the N-CDs, and the X-ray diffraction pattern showed that the N-CDs were crystalline, depicted with sharp peaks. This research work demonstrated that palm kernel shell biomass often thrown away as waste can produce CDs with excellent physicochemical properties.

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Tribological performance of various metal-doped carbon dots as water-based lubricant additives and their potential application as additives of poly(ethylene glycol)

Friction ◽

10.1007/s40544-020-0483-z ◽

2021 ◽

Author(s):

Weiwei Tang ◽

Xuejun Zhu ◽

Yufeng Li

Keyword(s):

Ethylene Glycol ◽

Tribological Properties ◽

Carbon Dots ◽

Lubricant Additives ◽

Poly Ethylene Glycol ◽

Wear Properties ◽

Water Based ◽

Friction Reducing ◽

Poly Ethylene ◽

Metal Doped

AbstractAdvances in nano-lubricant additives are vital to the pursuit of energy efficiency and sustainable development. Carbon dots (CDs) have been widely investigated in the domain of lubricant additives owing to their extraordinary tribological properties, in particular, their friction-reducing and anti-wear properties. Metal-doped CDs are a new type of CDs, and their friction-reducing and anti-wear properties are attracting increasing attention. Therefore, a series of CDs doped with various divalent metal ions have been successfully synthesized via one-pot pyrolysis. The tribological properties of the synthesized CDs as water-based lubricant additives are in the following order: Zn-CDs > Cu-CDs ≫ Mg-CDs > Fe-CDs > U-CDs. Specifically, adding 1.0 wt% of Zn-CDs into water-based lubricant results in 62.5% friction and 81.8% wear reduction. Meanwhile, the load-carrying capacity of the water-based lubricant increases from 120 N to at least 500 N. Zn-CDs as an additive have long service life. Additionally, anion-tuned Zn-CDs fabricated via anion exchange exhibit promise as lubricant additives for poly(ethylene glycol). Based on the results of wear scar surface analyses, it is discovered that tribochemical films, primarily composed of iron oxides, nitrides, metal carbonates, zinc oxides, zinc carbonates, organic compounds, and embedded carbon cores, formed on the rubbing surfaces with a thickness of approximately 270 nm when Zn-CDs are used as additives. This film combined with the “ball-bearing” and third-particle effects of Zn-CDs contributed to excellent lubrication performance.

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A green synthetic route for the surface-passivation of carbon dots as an effective multifunctional fluorescent sensor for the recognition and detection of toxic metal ions from aqueous solution

Analytical Methods ◽

10.1039/c8ay02451k ◽

2019 ◽

Vol 11 (4) ◽

pp. 490-506 ◽

Cited By ~ 10

Author(s):

K. Radhakrishnan ◽

P. Panneerselvam ◽

M. Marieeswaran

Keyword(s):

Aqueous Solution ◽

Quantum Dots ◽

Carbon Dots ◽

Surface Passivation ◽

Fluorescent Sensor ◽

Toxic Metal ◽

Carbon Quantum Dots ◽

Synthetic Route ◽

One Pot ◽

Hydrothermal Methods

In this work, a green synthetic route was used to create a number of surface passivated fluorescent carbon quantum dots, which are explored as promising sensing probes, via facile one-pot hydrothermal methods.

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One-pot synthesis of double silane-functionalized carbon dots with tunable emission and excellent coating properties for WLEDs application

Nanotechnology ◽

10.1088/1361-6528/ac4067 ◽

2021 ◽

Author(s):

Wenbing Cao ◽

Yuhan Wu ◽

Xin Li ◽

Xuanfeng Jiang ◽

Yuhong Zhang ◽

...

Keyword(s):

Optical Properties ◽

Carbon Dots ◽

Great Influence ◽

Alkoxy Group ◽

Color Temperature ◽

Molar Ratio ◽

Coating Properties ◽

One Pot ◽

Light Emitting ◽

Light Emitting Devices

Abstract Silane-functionalized carbon dots (SiCDs) can be exploited as effective color converting materials for the solid-state light-emitting devices. However, most of SiCDs reported thus far have shown photoluminescence emissions in the blue and green spectral range, which limit them to construct an efficient white light-emitting diodes (WLEDs) due to the lack of long-wavelength emission. Herein, a series of double silane-functionalized carbon dots (DSiCDs) were prepared via a one-step solvothermal method. The results show that the organic functional group of the silane has great influence on the optical properties of DSiCDs and the number of alkoxy group in the silane has great influence on coating properties of DSiCDs. In addition, the DSiCDs prepared by (3-aminopropyl)triethoxysilane and N-[3-(Trimethoxysilyl)propyl]ethylenediamine with molar ratio of 7:3 show excellent optical properties with the maximum emission at 608 nm under 400 nm excitation. Furthermore, they can be completely dried within 1 h at room temperature to form fluorescent coating with high stability and strong adhesion to the substrate. Together with their excellent optical and coating properties, they can be directly coated on LED chips to prepare WLEDs, with a CIE coordinate of (0.33,0.31), color rendering index of 81.6, and color temperature of 5774 K.

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Spectrofluorimetric Determination of Hydrochlorothiazide by a Carbon Dots-Based Probe via Inner Filtering Effect and Resonance Rayleigh Scattering

Journal of the Brazilian Chemical Society ◽

10.21577/0103-5053.20210155 ◽

2022 ◽

Author(s):

Ali Ghafarloo ◽

Reza Sabzi ◽

Naser Samadi ◽

Hamed Hamishehkar

Keyword(s):

Carbon Dots ◽

Rayleigh Scattering ◽

Limit Of Detection ◽

Fluorescent Sensor ◽

Emission Spectra ◽

Cost Effective ◽

Inner Filter Effect ◽

Resonance Rayleigh Scattering ◽

Excitation Spectra ◽

One Pot

Synthesis of carbon dots (CDs) from natural resources not only enables green synthesis and production of environmentally friendly materials, but also provides a cost-effective probe as a fluorescence nanosensor. The proposed sensor introduces a unique one-pot hydrothermal CDs synthesis from alfalfa leaves, which is promising for sensing hydrochlorothiazide (HCTZ) via inner filter effect (IFE) and resonance Rayleigh scattering (RRS). The as-prepared CDs had wide emission spectra, excitation-dependent emission, high solubility, high stability, and visible fluorescence light with a quantum yield of up to 11%. The absorption of HCTZ overlapped with the excitation spectra of CDs. Therefore, CDs represented excellent quenching due to IFE when HCTZ was gradually added. Furthermore, this fluorescent sensor was successfully used to quantify HCTZ in the linear ranges (0.17-2.50 μg mL-1) with the limit of detection of 0.11 μg mL-1. The sensing system was simple as no surface functionalization was required for CDs, leading to less laborious steps and more cost-effective synthesis. The reaction time was short, i.e., less than 2 min, indicating a simple approach for rapid analysis of HCTZ. By optimizing conditions, successful measurements were carried out on pharmaceutical tablets.

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