Preparation and Characterization of Graphite Oxide

2013 ◽  
Vol 771 ◽  
pp. 3-6 ◽  
Author(s):  
Zhao Xia Hou ◽  
Yin Zhou ◽  
Shao Hong Wang ◽  
Mei Han Wang ◽  
Xiao Dan Hu ◽  
...  

The preparation of graphite oxide is one of essential steps for graphene by oxidation reduction method. Graphite oxide was acquired from the oxidation of graphite by improved Hummers method and characterized by X-ray diffraction, scanning electron microscope, Fourier transform infrared absorbance spectroscopy and thermogravimetric analysis. It was showed that the graphite interlayer distance of graphite oxide increased for a large amount of oxygen containing functional groups. Shift and broaden of diffraction peaks were observed after oxidation and the original graphite peaks disappeared.

2013 ◽  
Vol 807-809 ◽  
pp. 2805-2808
Author(s):  
Zhao Xia Hou ◽  
Yin Zhou ◽  
Shao Hong Wang ◽  
Mei Han Wang ◽  
Xiao Dan Hu ◽  
...  

Graphene was prepared by using hydrazine hydrate to reduce the exfoliated graphite oxide nanosheets in the aqueous colloidal suspension. The prepared graphene were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD) and scanning electron microscope (SEM), respectively. The results showed that part of oxygen containing groups of the exfoliated graphite oxide nanosheets disappeared and the conjugated p bond recovered after reduction. The thickness and size of the graphene nanosheets decreased.


2013 ◽  
Vol 27 (19) ◽  
pp. 1341005
Author(s):  
YUHONG ZHANG ◽  
BIAO YAN ◽  
WEI LU

Graphite oxide was prepared by Hummers method, then it was obtained by ultrasound. Finally, graphene was prepared by using hydrazine hydrate as reducing agent. We can get the influences of oxidation time on the graphene structure by different reacting times. Ultrasonication can reduce the aggregation of graphene efficiently. The morphology and size of graphene were characterized by SEM, TEM, XRD and FTIR. Through this method, we can get high quality graphene which has smooth surface and fewer defects. The longer the oxidation time, the more easier it is to peel and insert functional groups.


2021 ◽  
Vol 1026 ◽  
pp. 117-121
Author(s):  
Zheng Miao ◽  
Rong Xia Zhu ◽  
Li Xia Zhang

Graphite oxide was prepared from 325 mesh graphite (G) in this paper with methods of Hummers method,sulphuric/phosphoric acid method and reaction kettle method, the Graphene Oxides (GO) were obtained with ultrasonic treatment. Then Fe3O4 particles of two different proportions and hydrazine hydrate were introduced into one of the GO to obtain GO/Fe3O4 composites. X-ray diffraction (XRD) was used to characterize the G,the obtained graphite oxide and GO/Fe3O4 respectively. Scanning electron microscopy (SEM) was used to characterize the obtained GO and GO/ Fe3O4 composites.The results show that the GO obtained by the way of sulphuric/phosphoric acid has the best pattern and the nanoparticle scale decreased as the proportion of GO in GO/Fe3O4 increased.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


2012 ◽  
Vol 620 ◽  
pp. 314-319
Author(s):  
Nur Amira Mamat Razali ◽  
Fauziah Abdul Aziz ◽  
Saadah Abdul Rahman

Hardwood is wood from angiosperm trees. The characteristic of hardwood include flowers, endosperm within seeds and the production of fruits that contain the seeds. This paper aims to discuss the preparation and characterization of cellulose obtained from hardwood. The hardwood Merbau (Intsia bijuga) was chosen as raw material in this study. Alkaline treatment and delignification methods were used for the preparation of cellulose. Acid hydrolysis was employed to produce cellulose nanocrystal (CNC). The treated and untreated samples were characterized using x-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The final product, from both trated and untreated samples were then compared.


2012 ◽  
Vol 174-177 ◽  
pp. 508-511
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang ◽  
Xiao Feng Wang

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.


1989 ◽  
Vol 4 (6) ◽  
pp. 1320-1325 ◽  
Author(s):  
Q. X. Jia ◽  
W. A. Anderson

Effects of hydrofluoric acid (HF) treatment on the properties of Y–Ba–Cu–O oxides were investigated. No obvious etching of bulk Y–Ba–Cu–O and no degradation of zero resistance temperature were observed even though the oxides were placed into 49% HF solution for up to 20 h. Surface passivation of Y–Ba–Cu–O due to HF immersion was verified by subsequent immersion of Y–Ba–Cu–O in water. A thin layer of amorphous fluoride formed on the surface of the Y–Ba–Cu–O during HF treatment, which limited further reaction between Y–Ba–Cu–O and HF, and later reaction with water. Thin film Y–Ba–Cu–O was passivated by HF vapors and showed no degradation in Tc-zero after 30 min immersion in water. The properties of the surface layer of Y–Ba–Cu–O oxide after HF treatment are reported from Auger electron spectroscopy, x-ray diffraction, and scanning electron microscopy studies.


2021 ◽  
pp. 004051752110154
Author(s):  
Zhihui Qin ◽  
Shuyuan Zhao ◽  
Liu Liu ◽  
Zhaohe Shi ◽  
Longdi Cheng ◽  
...  

Degumming is the dominant method for insolating lignocellulosic fibers in textile applications. Traditional alkaline degumming (TAL), as a common method, requires a high-concentration alkali and has been a severe challenge to the environment. In the research reported here, the possibility of innovative jute degumming by organic solvents 1-2 propylene glycol and a combination of additive green oxygen (GO-OS) was studied. The results revealed that fibers could be extracted by this system (under condition of 0.9% GO-OS, 180°C, 120 min), and obtained fibers with higher breaking tenacity (7.1 cN/dtex), yield (65.7%), breaking elongation (2.87%) and residual gum (11.7%), which all meet the requirement of the relevant Chinese Textile National Standards. Notably, the required reaction time (120 min) of the GO-OS system was 180 min shorter than that of the TAL method. Furthermore, the modifications introduced by the degumming effect on physicochemical aspects were characterized and confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. This study provides a promising degumming method for separating jute lignocellulose without acid and alkali consumption.


2022 ◽  
Vol 321 ◽  
pp. 126326
Author(s):  
Gladis Aparecida Galindo Reisemberger de Souza ◽  
Ramón Sigifredo Cortés Paredes ◽  
Frieda Saicla Barros ◽  
Gustavo Bavaresco Sucharski ◽  
Sebastião Ribeiro Junior ◽  
...  

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