From Graphite to Porous Carbon Containing Nanoparticles through Chemical Reactions

1996 ◽  
Vol 431 ◽  
Author(s):  
C. C. Hung ◽  
J. Corbin
Keyword(s):  
Metal Oxides ◽  
Surface Area ◽  
Porous Carbon ◽  
Chemical Properties ◽  
Atomic Ratio ◽  
Synthesis Process ◽  
Metal Chlorides ◽  
Graphite Fluoride ◽  
Surface Areas ◽  
Individual Nanoparticles

AbstractPorous carbon containing large quantities of separated individual nanoparticles (2–100 nm) was produced. The chemical process includes fluorination or oxygenation of graphite, and then exposing the product (graphite fluoride or graphite oxide) to metal chlorides. The nanoparticles were metal halides or metal oxides, which could contain dopants if they were added during the synthesis process. The metal to carbon atomic ratio was in the range of 1 (3–6). The chlorides used in this research include those of Pd, Zn, Al and Li. Depending on the synthesis process, the carbon pores could be either filled with the nanoparticles, resulting in near-zero surface area and high metal concentration, or partially filled with nanoparticles, resulting in large surface areas. In this report, near zero surface areas were observed for a product of LiCl in carbon, and a surface area of 75 m2/g was observed for the product of γ- Al2O3 in carbon. Heating these products in 1 atm air allowed the nanoparticles to become fuse together in the form of metal oxide while the carbon was oxidized, producing metal oxides which have the same shape as the carbon precursors (fibers, fabrics, or powder) and large surface areas. These products are potentially useful in the area of batteries, high temperature gas sensors, and catalysts. Also, these products could be used to examine individual nanopartidles, whose electrical, optical, and chemical properties differ from those of their single crystal or amorphous counterparts

Preparing high surface area porous carbon from biomass by carbonization in a molten salt medium

RSC Advances ◽  
2015 ◽  
Vol 5 (92) ◽  
pp. 75728-75734 ◽  
Author(s):  
Huishan Shang ◽  
Yanjie Lu ◽  
Feng Zhao ◽  
Cong Chao ◽  
Bing Zhang ◽  
...  
Keyword(s):  
Molten Salt ◽  
Surface Area ◽  
Porous Carbon ◽  
High Surface ◽  
High Surface Area ◽  
Molten Salt Synthesis ◽  
Synthesis Process ◽  
Salt Medium ◽  
Peanut Shells

Peanut shells were transformed into porous carbon with a high surface area through a simple ZnCl2-molten salt synthesis process.

A simple self-assembly strategy for ultrahigh surface area nitrogen-doped porous carbon nanospheres with enhanced adsorption and energy storage performances

2017 ◽  
Vol 53 (50) ◽  
pp. 6764-6767 ◽  
Author(s):  
Zhiwei Tang ◽  
Shaohong Liu ◽  
Zhitao Lu ◽  
Xidong Lin ◽  
Bingna Zheng ◽  
...  
Keyword(s):  
Energy Storage ◽  
Surface Area ◽  
Porous Carbon ◽  
Self Assembly ◽  
Carbon Nanospheres ◽  
Nitrogen Doped ◽  
Assembly Strategy ◽  
Surface Areas ◽  
Enhanced Adsorption ◽  
Porous Carbon Nanospheres

Versatile N-doped porous carbon nanospheres with ultrahigh surface areas were prepared based on copolymerization-induced self-assembly.

scholarly journals Synthesis and Characterization of an Iron Nitride Constructed by a Novel Template of Metal Organic Framework

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Suyan Liu ◽  
Quan Huo ◽  
Rongna Chen ◽  
Peipei Chen ◽  
Yuan Li ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Surface Area ◽  
Metal Organic Framework ◽  
Iron Nitrides ◽  
Synthesis Process ◽  
Iron Nitride ◽  
Transition Metal Nitrides ◽  
Surface Areas ◽  
Metal Organic ◽  
Organic Framework

An iron nitride with high surface area was synthesized from an iron-based metal organic framework (Fe-MOF) in this work. During the synthesis process, the Fe-MOF of MIL-53 served as a hard template, a template to impart a certain degree of morphology for iron oxide products and to form porosities for iron nitride products. Moreover, it played the roles of iron sources for the synthesis of the final iron oxides and the iron nitrides. The physicochemical properties of the materials were characterized by a series of technologies including XRD, SEM, and N2-adsorption/desorption. The results showed that the iron nitride synthesized from MIL-53 wasα-Fe2-3N. And, theα-Fe2-3N showed the morphology with loosely aggregated particles which favored the formation of rich interparticle porosities. As a result, the surface area of theα-Fe2-3N was larger than those of samples usingα-Fe2O3as precursors and its value was 41 m2/g. In addition, the results agreed that both raw material properties (such as crystallinity and surface areas) and nitriding approaches had significant effects on the surface areas of iron nitrides. Also the results were proved by the iron oxide synthesized with different methods. This new synthetic strategy could be a general approach for the preparation of late transition metal nitrides with peculiar properties.

Relationship Between Particle Size Distribution and Specific Surface Area of Urban Roadway Stormwater Solids

1997 ◽  
Vol 1601 (1) ◽  
pp. 95-108 ◽  
Author(s):  
John J. Sansalone ◽  
Steven G. Buchberger ◽  
Joseph M. Koran ◽  
Joseph A. Smithson
Keyword(s):  
Particle Size ◽  
Specific Surface ◽  
Surface Area ◽  
Particle Surface ◽  
Chemical Properties ◽  
Spherical Particles ◽  
Particle Surface Area ◽  
Surface Areas ◽  
Physical And Chemical ◽  
And Chemical Properties

Surface area is a primary factor in determining many physical and chemical properties of solids, especially particles. In urban and highway runoff, solids can mediate the partitioning between the dissolved and particulate-bound phases of metal elements and organic compounds. Solids are also capable of adversely affecting roadway drainage appurtenances through sedimentation and clogging. Solids characteristics of primary importance for both solute adsorption and clogging and sedimentation are particle size distributions (PSDs), specific surface areas (SSAs), and mass loadings. PSD and SSA results are presented for rainfall and snowmelt solids from a heavily traveled urban roadway in Cincinnati. Integration of the PSD and SSA results indicates that particle surface area is greatest for the midrange (> 100 μm) to the coarser end (<2000 μm) of the gradation. SSA results determined using the assumption of smooth spherical particles are indicated to grossly underestimate actual SSA values.

scholarly journals Facile Synthesis of Super-Microporous Titania–Alumina with Tailored Framework Properties

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1126
Author(s):  
Yongfeng Li ◽  
Jiaojiao Su ◽  
Guiping Li ◽  
Xiufeng Meng
Keyword(s):  
Pore Size ◽  
Surface Area ◽  
Self Assembly ◽  
Bet Surface Area ◽  
Synthesis Process ◽  
Tetrabutyl Titanate ◽  
One Pot ◽  
Microporous Material ◽  
Surface Areas ◽  
Fatty Alcohol Polyoxyethylene Ether

Super-microporous material (pore size 1–2 nm) can bridge the pore size gap between the zeolites (<1 nm) and the mesoporous oxides (>2 nm). A series of super-microporous titania–alumina materials has been successfully prepared via a facile one-pot evaporation-induced self-assembly (EISA) strategy by different solvents using fatty alcohol polyoxyethylene ether (AEO-7) as the template. Moreover, no extra acid or base is added in our synthesis process. When titanium isopropylate is used as the titanium source, these materials exhibit high BET surface areas (from 275 to 396 m2/g) and pore volumes (from 0.14 to 0.18 cm3/g). The sample prepared using methanol as the solvent shows the largest Brunauer–Emmett–Teller (BET) surface area of 396 m2/g. When tetrabutyl titanate is used as the titanium source, these materials exhibit high BET surface areas (from 282 to 396 m2/g) and pore volumes (from 0.13 to 0.18 cm3/g). The sample prepared using ethanol as the solvent shows the largest BET surface area of 396 m2/g.

scholarly journals Metaloxide Nanomaterials and Nanocomposites of Ecological Purpose

2019 ◽  
Vol 2019 ◽  
pp. 1-31 ◽  
Author(s):  
Tetiana A. Dontsova ◽  
Svitlana V. Nahirniak ◽  
Ihor M. Astrelin
Keyword(s):  
Metal Oxide ◽  
Metal Oxides ◽  
Chemical Properties ◽  
Correct Selection ◽  
Synthesis Methods ◽  
Main Task ◽  
Environmental Technologies ◽  
Nanoparticles Of Metal Oxides ◽  
Individual Nanoparticles ◽  
Physical And Chemical

The features of the properties and creation of nanocomposite metal oxide materials, especially TiO2, ZnO, SnO2, ZrO2, and Fe3O4, and their applications for ecology are considered in the article. It is shown that nanomaterials based on them are very promising for use in the ecological direction, especially as sorbents, photocatalysts, and sensitive layers of gas sensors. The crystallochemical characteristics, surface structure, and surface phenomena that occur when they enter the water and air environment are given for these metal oxides, and it is shown that they play a significant role in obtaining the sorption and catalytic characteristics of these nanomaterials. Particular attention is paid to the dispersion and morphology of metal oxide particles by which their physical and chemical properties can be controlled. Synthesis methods of metal oxide nanomaterials and ways for creating of nanocomposites based on them are characterized, and it is noted that there are many methods for obtaining individual nanoparticles of metal oxides with certain properties. The main task is the correct selection and testing of parameters. The prospects for the production of metal oxide nanocomposites and their application for environmental applications are noted, which will lead to a fundamentally new class of materials and new environmental technologies with their participation.

Formation and Applications of Hierarchically Porous Carbon, Metals and Metal Oxides Formed by Nanocasting

2012 ◽  
Vol 1389 ◽  
Author(s):  
Franchessa M. Sayler ◽  
Amy J. Grano ◽  
William Scogin ◽  
Pasha Sanders ◽  
Jan-Henrik Smått ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Metal Oxides ◽  
Porous Carbon ◽  
Porous Silica ◽  
Ionic Conductors ◽  
Hierarchically Porous ◽  
Surface Areas ◽  
Wide Range ◽  
Hierarchically Porous Materials ◽  
Silica Template

ABSTRACTHierarchically porous materials are of interest in a wide range of applications. If the materials are electronic or ionic conductors such materials are of interest as electrodes for use in fuel cells, flow batteries, electrocatalysis, and pseudo/supercapacitors. We have demonstrated the synthesis of hierarchically porous carbon, metal and metal oxide monoliths. Hierarchically porous silica with porosity at three length scales: 0.5-30 micrometer, 200-500 nm, and 3-8 nm, is used as a template to form these materials. The porosity of the silica template is produced by spinodal decomposition (0.5-30 micrometer), particle agglomeration (200-500 nm) and addition of surfactant or block copolymer (3-8 nm). Nanocasting: replication of all or part of the structure via one of a number of chemical replication techniques has been used to produce the carbon, metal oxide and metal replicas. The final surface areas of the materials can be as high as 1200 m2/g for carbon replicas, and >300 m2/g for metals and metal oxides. The use of the nanocasting technique allows for formation of materials that are compositionally or spatially heterogeneous.We report here results on the synthesis and characterization of hierarchically porous monoliths of carbon and, nickel and the use of some of these monoliths in catalysis and electrochemical capacitors.

Cell morphology, volume, and surface area determinations from multilevel contouring within HVEM micrographs of serial sections and whole-cell mounts

1987 ◽  
Vol 45 ◽  
pp. 588-589
Author(s):  
M. Marko ◽  
A. Leith ◽  
D. Parsons
Keyword(s):  
Surface Area ◽  
Electron Micrographs ◽  
Cell Morphology ◽  
Individual Variation ◽  
Serial Section ◽  
Stereo Pair ◽  
Complex Structures ◽  
Serial Sections ◽  
Surface Areas ◽  
Computer Based

The use of serial sections and computer-based 3-D reconstruction techniques affords an opportunity not only to visualize the shape and distribution of the structures being studied, but also to determine their volumes and surface areas. Up until now, this has been done using serial ultrathin sections.The serial-section approach differs from the stereo logical methods of Weibel in that it is based on the Information from a set of single, complete cells (or organelles) rather than on a random 2-dimensional sampling of a population of cells. Because of this, it can more easily provide absolute values of volume and surface area, especially for highly-complex structures. It also allows study of individual variation among the cells, and study of structures which occur only infrequently.We have developed a system for 3-D reconstruction of objects from stereo-pair electron micrographs of thick specimens.

scholarly journals Tuning the hierarchical pore structure of graphene oxide through dual thermal activation for high-performance supercapacitor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jeongpil Kim ◽  
Jeong-Hyun Eum ◽  
Junhyeok Kang ◽  
Ohchan Kwon ◽  
Hansung Kim ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Pore Structure ◽  
Specific Capacitance ◽  
Surface Area ◽  
Thermal Annealing ◽  
High Performance ◽  
Annealing Process ◽  
Supercapacitor Electrode ◽  
Simple Method ◽  
Surface Areas

AbstractHerein, we introduce a simple method to prepare hierarchical graphene with a tunable pore structure by activating graphene oxide (GO) with a two-step thermal annealing process. First, GO was treated at 600 °C by rapid thermal annealing in air, followed by subsequent thermal annealing in N2. The prepared graphene powder comprised abundant slit nanopores and micropores, showing a large specific surface area of 653.2 m2/g with a microporous surface area of 367.2 m2/g under optimized conditions. The pore structure was easily tunable by controlling the oxidation degree of GO and by the second annealing process. When the graphene powder was used as the supercapacitor electrode, a specific capacitance of 372.1 F/g was achieved at 0.5 A/g in 1 M H2SO4 electrolyte, which is a significantly enhanced value compared to that obtained using activated carbon and commercial reduced GO. The performance of the supercapacitor was highly stable, showing 103.8% retention of specific capacitance after 10,000 cycles at 10 A/g. The influence of pore structure on the supercapacitor performance was systematically investigated by varying the ratio of micro- and external surface areas of graphene.

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