The Effect of Different Ratio in Carbon Aerogel on Pore Structure in Ambient Dry

2014 ◽  
Vol 941-944 ◽  
pp. 450-453 ◽  
Author(s):  
Fang Wang ◽  
Lan Fang Yao ◽  
Jun Shen ◽  
Da Yong Guan ◽  
Zhou Fang
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Ambient Pressure ◽  
Sol Gel ◽  
Carbon Aerogel ◽  
Surface Characteristic ◽  
Carbon Aerogels ◽  
Water Solvent ◽  
Organic Aerogels

Organic aerogels were prepared by sol-gel polycondensation of resorcinol and formaldehyde using sodium carbonate as a catalyst and dried under ambient pressure. Carbon aerogels were obtained by the dried organic aerogels carbonized under nitrogen atmosphere at high temperature. The pore structures and surface characteristic of the carbon aerogels obtained were investigated by N2 adsorption isotherms, scanning electron microscope (SEM). Through controlling the concentrations of the main ingredients (resorcinol and formaldehyde), catalyst concentration, we can find out the best concentration which the specific surface area can reach the highest. In this experiment the highest specific surface area was 1645m2/g. In addition, the results show that catalyst for the cross link effect between colloidal microspheres is greater than the growth of the colloid itself, and the effect of water solvent plays an important role in the density of carbon aerogel.

Preparation and Characterization of Phloroglucinol-Resorcinol-Formaldehyde Carbon Aerogels

2013 ◽  
Vol 423-426 ◽  
pp. 523-527
Author(s):  
Xuan Liu ◽  
Zhen Fa Liu ◽  
Hao Lin Fu ◽  
Rui He ◽  
Li Hui Zhang
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Sol Gel ◽  
High Specific Surface Area ◽  
Carbon Aerogels ◽  
Resorcinol Formaldehyde ◽  
Sol Gel Process ◽  
Solvent Replacement ◽  
Organic Aerogels

Phloroglucinol-resorcinol-formaldehyde organic aerogels (PRF) were prepared using phloroglucinol, resorcinol and formaldehyde in a sol-gel process, solvent replacement and drying at room temperature. The phloroglucinol-resorcinol-formaldehyde carbon aerogels (CPRF) were prepared by charring the PRF at high temperature under the aegis of helium flow. The microstructure of CPRF was characterized by infrared spectroscopy, specific surface area analyzer and scanning electron microscopy. The results showed that the CPRF had continuous network structure and high specific surface area.

scholarly journals Enhanced capacitive performance by improving the graphitized structure in carbon aerogel microspheres

RSC Advances ◽  
2020 ◽  
Vol 10 (37) ◽  
pp. 22242-22249
Author(s):  
Xichuan Liu ◽  
Lei Yuan ◽  
Minglong Zhong ◽  
Shuang Ni ◽  
Fan Yang ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
High Temperature ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Carbon Aerogel ◽  
High Specific Surface Area ◽  
Activation Method ◽  
Carbon Aerogels ◽  
Capacitive Performance

Carbon aerogels (CAs) microspheres with good electrical conductivity and high specific surface area were synthesized by high temperature carbonization and CO2 activation method, which exhibit an enhanced capacitive performance in supercapacitors.

scholarly journals Characteristics of carbon aerogel at variation in pyrolysis conditions

2016 ◽  
Vol 19 (3) ◽  
pp. 88-95
Author(s):  
Duyen Khac Le ◽  
Nghiep Quoc Pham ◽  
Kien Anh Le
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Pyrolysis Temperature ◽  
Ambient Pressure ◽  
Total Pore Volume ◽  
Nitrogen Adsorption ◽  
Carbon Aerogel ◽  
Ambient Pressure Drying ◽  
Xrd Diffraction

Carbon aerogel was obtained by pyrolysis of organic aerogel by ambient pressure drying technique. The effect of pyrolysis conditions on characteristics of carbon aerogel such as density, specific surface area and conductivity was studied. The properties and structure of carbon aerogel samples were investigated by nitrogen adsorption, four-point probe method and XRD diffraction. The results showed that carbon aerogel had structure between amorphous and graphite state. The highest specific surface area was 800 m2/g at pyrolysis temperature of 700oC. The pore-size was distributed in microporous, with the maximum total pore volume of 0.44 cm3/g. The electrical conductivity of carbon aerogel was highest at pyrolysis temperature of 800-900oC with the value in the range of 1.744-1.923 S/cm.

scholarly journals Tuning the Morphological Properties of Cellulose Aerogels: An Investigation of Salt-Mediated Preparation

2021 ◽  
Author(s):  
Prakash Parajuli ◽  
Sanjit Acharya ◽  
Julia Shamshina ◽  
Noureddine Abidi
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Sol Gel ◽  
Earth Metal ◽  
Morphological Properties ◽  
Cellulose Solution ◽  
Bet Analysis ◽  
Sol Gel Transition ◽  
Gel Transition

Abstract In this study, alkali and alkaline earth metal chlorides with different cationic radii (LiCl, NaCl, and KCl, MgCl2, and CaCl2) were used to gain insight into the behavior of cellulose solutions in the presence of salts. The specific focus of the study was evaluation of the effect of salts’ addition on the sol-gel transition of the cellulose solutions and on their ability to form monoliths, as well as evaluation of the morphology (e.g., specific surface area, pore characteristics, and microstructure) of aerocelluloses prepared from these solutions. The effect of the salt addition on the sol-gel transition of cellulose solutions was studied using rheology, and morphology of resultant aerogels was evaluated by Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, while the salt influence on the aerocelluloses’ crystalline structure and thermal stability was evaluated using powder X-Ray Diffraction (pXRD) and Thermogravimetric Analysis (TGA), respectively. The study revealed that the effect of salts’ addition was dependent on the component ions and their concentration. The addition of salts in the amount below certain concentration limit significantly improved the ability of the cellulose solutions to form monoliths and reduced the sol-gel transition time. Salts of lower cationic radii had a greater effect on gelation. However, excessive amount of salts resulted in the formation of fragile monoliths or no formation of gels at all. Analysis of surface morphology demonstrated that the addition of salts resulted in a significant increase in porosity and specific surface area, with salts of lower cationic radii leading to aerogels with much larger (~1.5 and 1.6-fold for LiCl and MgCl2, respectively) specific surface area compared to aerocelluloses prepared with no added salt. Thus, by adding the appropriate salt into the cellulose solution prior to gelation, the properties of aerocelluloses that control material’s performance (specific surface area, density, and porosity) could be tailored for a specific application.

scholarly journals Synthesis of Spherical Silica by Sol-Gel Method and Its Application as Catalyst Support

2011 ◽  
Vol 10 (2) ◽  
pp. 25
Author(s):  
Anirut Leksomboon ◽  
Bunjerd Jongsomjit
Keyword(s):  
Particle Size ◽  
Ethylene Glycol ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Sol Gel ◽  
Weight Ratio ◽  
Gel Method ◽  
Sol Gel Method ◽  
Spherical Silica

In this present study, the spherical silica support was synthesized from tetraethyloxysilane (TEOS), water, sodium hydroxide, ethylene glycol and n-dodecyltrimethyl ammonium bromide (C12TMABr). The particle size was controlled by variation of the ethylene glycol co-solvent weight ratio of a sol-gel method preparation in the range of 0.10 to 0.50. In addition, the particle size apparently increases with high weight ratio of co-solvent, but the particle size distribution was broader. The standard deviation of particle diameter is large when the co-solvent weight ratio is more than 0.35 and less than 0.15. However, the specific surface area was similar for all weight ratios ranging from 1000 to 1300 m2/g. The synthesized silica was spherical and has high specific surface area. The cobalt was impregnated onto the obtained silica to produce the cobalt catalyst used for CO2 hydrogenation.</

Photocatalytic Efficiency for Dye Decolorization of the UV/TiO2, UV/TiO2 + In2O3 and UV/TiO2-In2O3 Systems

2013 ◽  
Vol 831 ◽  
pp. 263-266
Author(s):  
Chung Hsin Wu ◽  
Chao Yin Kuo ◽  
Chih Hao Lai ◽  
Wei Yang Chung
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Sol Gel ◽  
Dye Decolorization ◽  
X Ray Diffraction ◽  
First Order ◽  
First Order Kinetics ◽  
Vis Spectroscopy ◽  
Reactive Red 2

This study explored the decolorization of C.I. Reactive Red 2 (RR2) by the ultraviolet (UV)/TiO2, UV/TiO2 + In2O3, and UV/TiO2-In2O3 systems. The TiO2-In2O3 was generated by the sol-gel method and TiO2 + In2O3 was created by mixing TiO2 and In2O3 powders. The surface properties of TiO2, In2O3, and TiO2-In2O3 were analyzed by X-ray diffraction, a specific surface area analyzer, UV-vis spectroscopy, and scanning electron microscopy. The specific surface area of TiO2, In2O3, and TiO2-In2O3 was 29.5, 44.6, and 35.7 m2/g, respectively; additionally, the band gap of TiO2, In2O3, and TiO2-In2O3 was 2.95, 2.64, and 2.91 eV; respectively. The decolorization rate constant fit pseudo-first-order kinetics and that of the UV/TiO2, UV/TiO2 + In2O3, and UV/TiO2-In2O3 systems was 0.0023, 0.0031, and 0.0072 min-1; respectively.

Study of Heating Effect on Specific Surface Area, and Changing Optical Properties of ZnO Nanocrystals

2011 ◽  
Vol 403-408 ◽  
pp. 1205-1210
Author(s):  
Jaleh Babak ◽  
Ashrafi Ghazaleh ◽  
Gholami Nasim ◽  
Azizian Saeid ◽  
Golbedaghi Reza ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Energy Gap ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Transmission Electron ◽  
Zno Nanocrystal

In this work ZnO nanocrystal powders have been synthesized by using Zinc acetate dehydrate as a precursor and sol-gel method. Then the products have been annealed at temperature of 200-1050°C, for 2 hours. The powders were characterized using X-ray diffraction (XRD), UV-vis absorption and photoluminescence (PL) spectroscopy. The morphology of refrence ZnO nanoparticles have been studied using Transmission Electron Microscope (TEM). During the annealing process, increase in nanocrystal size, defects and energy gap quantitative, and decrease in specific surface area have been observed.

Frontiers of carbon materials as capacitive deionization electrodes

2020 ◽  
Vol 49 (16) ◽  
pp. 5006-5014 ◽  
Author(s):  
Yuanyuan Li ◽  
Nan Chen ◽  
Zengling Li ◽  
Huibo Shao ◽  
Liangti Qu
Keyword(s):  
Carbon Nanotubes ◽  
Activated Carbon ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Carbon Materials ◽  
High Specific Surface Area ◽  
Carbon Aerogels ◽  
Capacitive Deionization

Carbon materials are widely used as capacitive deionization (CDI) electrodes due to their high specific surface area (SSA), superior conductivity, and better stability, including activated carbon, carbon aerogels, carbon nanotubes and graphene.

scholarly journals Design and Photocatalytic Activity of Mesoporous TiO2/ZrO2 Thin Films

2005 ◽  
Vol 23 (6) ◽  
pp. 497-508 ◽  
Author(s):  
Yu. Gnatyuk ◽  
N. Smirnova ◽  
A. Eremenko ◽  
V. Ilyin
Keyword(s):  
Thin Films ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Surface Acidity ◽  
Sol Gel ◽  
Pluronic P123 ◽  
Vis Spectroscopy ◽  
Gel Technique ◽  
Doped Titania

Optically transparent, crack-free mesoporous titania and zirconia-doped titania thin films were fabricated by the sol—gel technique using the non-ionic amphiphilic triblock copolymer Pluronic P123 as the template. The structure and optical properties of these films were characterized using TEM, low-angle XRD, DTA/TG measurements, UV—vis spectroscopy and hexane adsorption investigations. It was found that addition of ZrO2 into the TiO2 matrix retarded sintering of the films, thereby increasing the specific surface area after treatment up to 500°C. The catalytic activity of the mesoporous TiO2 and TiO2/(5–30%) ZrO2 films in ethanol photo-oxidation increased with increasing specific surface area and surface acidity of the samples.

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