scholarly journals Study on Nitrogen-Doped Graphene Ink and Its Effects on the Heat Dissipation for the LED Lamps

2020 ◽  
Vol 10 (8) ◽  
pp. 2738
Author(s):  
Ah-Der Lin ◽  
Wen-Kai Yu ◽  
Sian Zheng Poon ◽  
Cheng-Yi Chen ◽  
Chao-Ming Hsu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Heat Dissipation ◽  
Light Emitting Diode ◽  
Short Circuit ◽  
High Heat ◽  
Integrating Sphere ◽  
Light Emitting ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene

This study explored the application of nitrogen-doped graphene (NDG) ink to the coating of light-emitting diode (LED) lamps for the thermal management. Unlike the general solutions of graphene, the NDG ink used in this study was tuned with high electrical resistance and quietly suitable for the application of the LED lamp coating, which prevented the short circuit problem; besides, the NDG ink also provided a high heat dissipation effect to improve the performance of the LED lamp. The investigation of adhesion and resistance for the NDG ink were conducted by the cross-cut test and the four-point probe resistance measurement, respectively. Three types of LED lamps including the original lamp, fin-removed lamp, and NDG-ink coated (NGC) lamp were tested for the actual operating temperature distribution by K-type thermal couples and for the lumens by the integrating sphere. The results showed that the heat dissipation of the NGC lamp was better than that of the original lamp. In addition, the inspections for the properties of NDG powder were also performed by x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and Raman spectroscopy. According to the inspectional results, the NDG powder had a percentage of nitrogen of about 3.8% by XPS, a surface roughness Rq of 0.9 nm by AFM, and over ten layers by Raman analysis. It showed that the NDG powder in this study belonged to the type of multi-layer graphene.

Hydrogenation and dehydrogenation of nitrogen-doped graphene investigated by X-ray photoelectron spectroscopy

2015 ◽  
Vol 634 ◽  
pp. 89-94 ◽  
Author(s):  
F. Späth ◽  
W. Zhao ◽  
C. Gleichweit ◽  
K. Gotterbarm ◽  
U. Bauer ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
X Ray ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene

Nitrogen-doped graphene quantum dots synthesized by femtosecond laser ablation in liquid from laser induced graphene

2021 ◽  
Author(s):  
Li Shen ◽  
Sikun Zhou ◽  
Fei Huang ◽  
Hao Zhou ◽  
Hong Zhang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Laser Ablation ◽  
Femtosecond Laser ◽  
Photoelectron Spectroscopy ◽  
Graphene Quantum Dots ◽  
Femtosecond Laser Ablation ◽  
Laser Ablation In Liquid ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene

Abstract In this work, graphene quantum dots (GQDs) synthesized by femtosecond laser ablation in liquid (LAL) using laser-induced graphene (LIG) as the carbon source. Nitrogen-doped graphene quantum dots (N-GQDs) were successfully synthesized by adding ammonia water to the graphene suspension. The GQDs/N-GQDs structure consist of a graphitic core with oxygen and nitrogen functionalities and particle size less than 10 nm, as demonstrated by X-ray photoelectron spectroscopy, Fourier infrared spectrometer spectroscopy and transmission electron microscopy. The absorption peak and PL spectrum and quantum yield of the N-GQDs were significantly enhanced compared with the undoped GQDs. Further, the possible mechanism of synthesis GQDs is discussed. Furthermore, the N-GQDs were used as a fluorescent probe for detection of Fe3+ ions. The N-GQDs may extend the application of graphene-based materials to bioimaging, sensor and, photoelectronic.

Fabrication and Electrochemical Performance of Nitrogen-Doped Graphene Synthesized by Hydrothermal Method

2014 ◽  
Vol 804 ◽  
pp. 35-38
Author(s):  
Sen Liang ◽  
Min Luo ◽  
Yuan Yun Dou ◽  
Lei Guo ◽  
Bin Liang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
Electrical Measurements ◽  
X Ray ◽  
Nitrogen Doped ◽  
Reduced Graphene ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene ◽  
Nitrogen Substitution ◽  
Pyridinic N

In this study, nitrogen doped graphene (NG) was prepared by using hydrothermal treatment of graphene oxide (GO) and ethylene diamine (EDA). The surface chemistry of the reduced graphene oxide (rGO) and the NG was investigated by the X-ray photoelectron spectroscopy (XPS). The results revealed that there were four kinds of nitrogen substitution: pyrollic N, pyridinic N, graphitic N and C-NH2. Further, the electrical measurements illustrated that the NG had superior capacitive performance than that of the rGO. Specifically, the maximum specific capacitance of NG was 200.6 F/g due to the double-layer capacitive and pseudocapacitive effect from the nitrogen-doped graphene. In addition, the present studies showed that the EDA was not only choose as nitrogen doping source but also played a key role in reduction.

scholarly journals Tailoring fluorescence emissions, quantum yields, and white light emitting from nitrogen-doped graphene and carbon nitride quantum dots

Nanoscale ◽  
2019 ◽  
Vol 11 (35) ◽  
pp. 16553-16561 ◽  
Author(s):  
Siyong Gu ◽  
Chien-Te Hsieh ◽  
Yasser Ashraf Gandomi ◽  
Jianlin Li ◽  
Xing Xing Yue ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Carbon Nitride ◽  
Solid Phase ◽  
Graphene Quantum Dots ◽  
Quantum Yields ◽  
Light Emitting ◽  
Nitrogen Doped ◽  
Microwave Assisted ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene

Highly fluorescent N-doped graphene quantum dots (NGQDs) and graphitic carbon nitride quantum dots (CNQDs, g-C3N4) were synthesized using a solid-phase microwave-assisted (SPMA) technique.

scholarly journals Efficient Removal of Bisphenol A Using Nitrogen-Doped Graphene-Like Plates from Green Petroleum Coke

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3543
Author(s):  
Zhipeng Liu ◽  
Quanyong Wang ◽  
Bei Zhang ◽  
Tao Wu ◽  
Yujiang Li
Keyword(s):  
Bisphenol A ◽  
Petroleum Coke ◽  
Photoelectron Spectroscopy ◽  
Oil Refining ◽  
Bet Surface Area ◽  
X Ray ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene ◽  
Green Petroleum Coke

Green petroleum coke, a form of industrial waste produced in the oil-refining process, was used to synthesize nitrogen-doped graphene-like plates (N-GLPs) together with melamine. In this study, characterization and batch experiments were performed to elucidate the interaction mechanism of N-GLPs and bisphenol A (BPA). Structural analysis of N-GLPs, including scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), showed an obvious graphene-like structure and successful nitrogen doping. In addition, compared with 8.0 m2/g for green petroleum coke, the BET surface area of N-GLPs markedly increased to 96.6 m2/g. The influences of various factors, including contact time, temperature, and initial pH on BPA removal efficiency were investigated. It was found that 92.0% of BPA was successfully removed by N-GLPs at 50 °C. Based on the adsorption experiments, it was shown that electrostatic attraction, hydrogen bonding, and π-π interaction enhanced the adsorption capacity of N-GLPs for BPA. According to the thermodynamic data, the adsorption process was spontaneous, physical, and endothermic in nature. Therefore, N-GLPs are efficient adsorbent material to remove BPA from wastewater.

A stacked structure comprising 3-dimensional nitrogen-doped graphene, silicon microchannel plate, and TiO2 for high-performance anode in lithium-ion battery

2019 ◽  
Vol 9 (6) ◽  
pp. 629-634 ◽  
Author(s):  
Fengjuan Miao ◽  
Rui Miao ◽  
Zang Yu ◽  
Cuiping Shi ◽  
Lei Zhu ◽  
...  
Keyword(s):  
Lithium Ion Battery ◽  
Photoelectron Spectroscopy ◽  
Active Sites ◽  
High Performance ◽  
Large Scale ◽  
Electrochemical Techniques ◽  
Lithium Ion ◽  
Nitrogen Doped ◽  
Nitrogen Doped Graphene ◽  
Doped Graphene

A hybrid electrode composed of silicon microchannel plates (Si MCPs) coated with nitrogen-doped graphene and TiO2 is prepared and used as the anode in a lithium-ion battery. The materials are characterized systematically by scanning electron microscopy, Raman scattering spectroscopy, X-ray photoelectron spectroscopy, and electrochemical techniques. The unique porous and ordered nanostructure of the TiO2/N-graphene/Si-MCP nanocomposite provides short paths for diffusion of Li ions and immobilized active sites, whereas N-doped graphene facilitates fast charge transportation. The synergetic effects result in high reversible specific capacities and stability. Owing to the compatibility with semiconductor processing and devices, the concept and technique have large potential in large-scale fabrication of high-performance anodes of lithium-ion batteries, especially those integrated into microelectronic chips.

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