ELECTROCHEMICAL STORAGE OF HYDROGEN IN CARBON NANOSTRUCTURES

2003 ◽  
Vol 02 (04n05) ◽  
pp. 307-317
Author(s):  
M. S. YU ◽  
S. Y. CHENG ◽  
Y. C. LIN ◽  
W. C. HO
Keyword(s):  
Carbon Nanostructures ◽  
Room Temperature ◽  
Hydrogen Adsorption ◽  
Abundance Ratio ◽  
Nanostructured Carbon ◽  
Half Cell ◽  
Carbonaceous Particles ◽  
Catalytic Thermal Decomposition ◽  
Electrochemical Storage ◽  
Preliminary Study

We have synthesized a set of nanostructured carbon samples including a variety of carbon nanotubes and carbonaceous particles, by catalytic thermal decomposition of CH4 on catalyst LaNi 5 powder with different reaction temperatures. Products obtained at reaction temperatures 550~900°C were characterized by means of HR-TEM, SEM and Raman Scattering. In addition, electrochemical charge–discharge cycling method was carried out at room temperature to measure the reversible hydrogen capacity in pressed electrodes containing mixture of catalyst, nanostructured carbon samples and carbonaceous particles. Results showed that the abundance ratio of well-crystallized graphite to amorphous carbon in each product increases with increasing reaction temperatures. This preliminary study showed also that the hydrogen storage capacity of synthesis products measured in an electrochemical half-cell at room temperature correlates with the nanostructure and morphology of the variety of nanostructured carbon samples. Additionally, the hydrogen adsorption capacity against specific surface area (BET) for synthesis products produced at temperatures higher than 670°C is ranging from 14 to 25 wt.%/(1000 m2/g).

Pressure Isotherms of Hydrogen Adsorption in Carbon Nanostructures

2001 ◽  
Vol 706 ◽  
Author(s):  
Xiaohong Chen ◽  
Urszula Dettlaff-Weglikowska ◽  
Miroslav Haluska ◽  
Martin Hulman ◽  
Siegmar Roth ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Activated Carbon ◽  
Hydrogen Storage ◽  
Carbon Nanostructures ◽  
Room Temperature ◽  
Storage Capacity ◽  
Hydrogen Adsorption ◽  
Single Wall Carbon Nanotubes ◽  
Hydrogen Storage Capacity ◽  
Carbon And Graphite

AbstractThe hydrogen adsorption capacity of various carbon nanostructures including single-wall carbon nanotubes, graphitic nanofibers, activated carbon, and graphite has been measured as a function of pressure and temperature. Our results show that at room temperature and a pressure of 80 bar the hydrogen storage capacity is less than 1 wt.% for all samples. Upon cooling, the capacity of hydrogen adsorption increases with decreasing temperature and the highest value was observed to be 2.9 wt. % at 50 bar and 77 K. The correlation between hydrogen storage capacity and specific surface area is discussed.

scholarly journals Review of Multi-Physics Modeling on the Active Magnetic Regenerative Refrigeration

2021 ◽  
Vol 26 (2) ◽  
pp. 47
Author(s):  
Julien Eustache ◽  
Antony Plait ◽  
Frédéric Dubas ◽  
Raynal Glises
Keyword(s):  
Magnetic Field ◽  
Low Temperatures ◽  
Room Temperature ◽  
State Of The Art ◽  
Vapor Compression ◽  
Crucial Step ◽  
Potential Alternative ◽  
Vapor Compression Refrigeration ◽  
Preliminary Study ◽  
Physics Modeling

Compared to conventional vapor-compression refrigeration systems, magnetic refrigeration is a promising and potential alternative technology. The magnetocaloric effect (MCE) is used to produce heat and cold sources through a magnetocaloric material (MCM). The material is submitted to a magnetic field with active magnetic regenerative refrigeration (AMRR) cycles. Initially, this effect was widely used for cryogenic applications to achieve very low temperatures. However, this technology must be improved to replace vapor-compression devices operating around room temperature. Therefore, over the last 30 years, a lot of studies have been done to obtain more efficient devices. Thus, the modeling is a crucial step to perform a preliminary study and optimization. In this paper, after a large introduction on MCE research, a state-of-the-art of multi-physics modeling on the AMRR cycle modeling is made. To end this paper, a suggestion of innovative and advanced modeling solutions to study magnetocaloric regenerator is described.

Piezoresistivity and Electrical Resistance Relaxation of Polyisoprene Nanostructured Carbon Allotrope Hybrid Composites

2015 ◽  
Vol 1117 ◽  
pp. 52-55
Author(s):  
Artis Linarts ◽  
Maris Knite
Keyword(s):  
Electrical Resistance ◽  
Room Temperature ◽  
Constant Pressure ◽  
Hybrid Composites ◽  
Conductive Filler ◽  
Force Sensor ◽  
Filler Concentration ◽  
Nanostructured Carbon ◽  
Carbon Allotrope ◽  
Resistance Relaxation

Polymer conductive filler composites are believed to be promising materials for flexible force sensor manufacture. Polyisoprene various carbon allotrope hybrid composites were made and their piezoresistive properties depending on the two type’s filler concentration and their ratio have been determined. Electrical resistance relaxations of hybrid composites at constant pressure in room temperature were determined as well. Experimental data of resistance relaxation was analyzed and fitted similarly to stress relaxation of polymers at constant pressure.

scholarly journals Carbon Nanosorbent for Purification Different Biomolecules

2011 ◽  
Vol 14 (1) ◽  
pp. 41
Author(s):  
Z.A. Mansurov ◽  
A.R. Kerimkulova ◽  
S.A. Ibragimova ◽  
E.Y. Gukenheimer
Keyword(s):  
Carbon Nanostructures ◽  
Large Scale ◽  
Carbon Materials ◽  
Raw Materials ◽  
Carbon Sorbent ◽  
Nanostructured Carbon ◽  
Lipid Complex ◽  
Carbon Sorbents ◽  
Physico Chemical ◽  
Chemical Studies

The article presents the results of physico-chemical studies on the development of nanostructured carbon materials from domestic raw materials. Were obtained and tested micro-mesoporous carbon sorbents for molecular-sieve chromatography of markers and investigated the applicability of carbon sorbents for the separation of protein-lipid complex, and plant bio-stimulator. Carbon sorbents have well-developed porous structure but their disadvantage is the weak mechanical<br />strength. Recently it was shown that some carbon nanostructures have enormous strength. Thus arose the need to give the nano structured elements to carbon sorbent. Creating carbon sorbents containing nanocarbon structure was the aim of our study, as these by sorbents will be very useful for large-scale purification of biomolecules.

scholarly journals Contribution Succinonitrile additive for Performa LiTFSi Solid Polymer Electrolytes for Li-Ion Battery

2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Qolby Sabrina ◽  
Titik Lestariningsih ◽  
Christin Rina Ratri ◽  
Achmad Subhan
Keyword(s):  
Ionic Conductivity ◽  
Polymer Electrolytes ◽  
Room Temperature ◽  
Lithium Salt ◽  
Ionic Conduction ◽  
Lithium Ion ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Half Cell ◽  
Li Ion

Solid polymer electrolyte (SPE) appropriate to solve packaging leakage and expansion volume in lithium-ion battery systems. Evaluation of electrochemical performance of SPE consisted of mixture lithium salt, solid plasticizer, and polymer precursor with different ratio. Impedance spectroscopy was used to investigate ionic conduction and dielectric response lithium bis(trifluoromethane)sulfony imide (LiTFSI) salt, and additive succinonitrile (SCN) plasticizer. The result showing enhanced high ionic conductivity. In half-cell configurations, wide electrochemical stability window of the SPE has been tested. Have stability window at room temperature, indicating great potential of SPE for application in lithium ion batteries. Additive SCN contribute to forming pores that make it easier for the li ion to move from the anode to the cathode and vice versa for better perform SPE. Pore of SPE has been charaterization with FE-SEM. Additive 5% w.t SCN shows the best ionic conductivity with 4.2 volt wide stability window and pretty much invisible pores.

scholarly journals A Preliminary Study on the Physical Properties of an Alternative Coarse Aggregate Made with Red Soil and Fly Ash

2018 ◽  
Vol 12 (1) ◽  
pp. 1-8
Author(s):  
J. Bright Brabin Winsley ◽  
M. Muthukannan
Keyword(s):  
Fly Ash ◽  
Specific Gravity ◽  
Room Temperature ◽  
Coarse Aggregate ◽  
Environmental Issues ◽  
Red Soil ◽  
Test Results ◽  
Ordinary Concrete ◽  
Preliminary Study ◽  
Natural Aggregates

Background and Objective: The demand for course aggregate is increasing every day. Natural aggregate used for ordinary concrete is obtained by quarrying, which cause serious environmental issues. An alternate course aggregate is needed for sustainable development. The objective of this research is to produce an alternative course aggregate in combination with soil available locally near site along with fly ash, to test its properties to make it fit for concrete. Method: An alternative coarse aggregate is produced from red soil and fly ash mixed at various ratios, 100:0, 90:10, 80:20, 70:30, 60:40, 50:50, fresh aggregate granules of different sizes less than 10mm is prepared using hand press, the aggregates were sundried in shade for 24hours, oven dried at 110°C, burned in Muffle furnace at temperature of 950°C and cooled gradually to reach room temperature. After the production, the specific gravity, bulk density, water absorption, Impact and aggregate crushing of the aggregates were tested. Result: Test results showed that aggregates produced are of lesser specific gravity, density with relatively appreciable impact value and crushing value. Conclusion: The test results show that the aggregates produced can be used in construction as replacement for natural aggregates.

Synthesis of a Novel Structure Carbon Nanocoils and their Application in Photo Diode Devices

2014 ◽  
Vol 1064 ◽  
pp. 89-94
Author(s):  
Mohammed Ibrahim Mohamed
Keyword(s):  
Thermal Decomposition ◽  
Atmospheric Pressure ◽  
Cylindrical Shape ◽  
The Novel ◽  
Stainless Steel Mesh ◽  
Forward Current ◽  
Novel Structure ◽  
Catalytic Thermal Decomposition ◽  
Tunneling Recombination ◽  
Preliminary Study

In this paper, the novel structure of carbon nanocoils were synthesized successfully by catalytic thermal decomposition of acetylene in CVD reactor under inert atmospheric pressure. Fe as a catalyst coated alumina beads used as substrate , both were placed inside a cylindrical shape stainless steel mesh SSC and located at the mid of CVD reactor. Preliminary study of application of prepared carbon nanocoil in synthesis of photodiode showed that the photodiode has a good rectification and the forward current obeys to tunneling-recombination model.

Preliminary Study of WO3 Nanostructures Produced via Facile Hydrothermal Synthesis Process for CO2 Sensing

2013 ◽  
Vol 431 ◽  
pp. 37-41 ◽  
Author(s):  
Amirul Abd Rashid ◽  
Nor Hayati Saad ◽  
Chia Sheng Daniel Bien ◽  
Wai Yee Lee ◽  
M.A.S.M. Haniff
Keyword(s):  
Room Temperature ◽  
Gas Sensing ◽  
Hydrothermal Reaction ◽  
Hydrothermal Process ◽  
Single Step ◽  
Synthesis Process ◽  
Sensor Element ◽  
Response Measurement ◽  
Sensor Fabrication ◽  
Preliminary Study

Tungsten trioxide (WO3) nanostructure with aspect ratio of 20 (length/diameter) have been successfully synthesized by single step hydrothermal reaction at moderate temperature of 180 °C. The crystal structure and morphology evolution are characterized by SEM and Raman while the carbon dioxide (CO2) sensing capability was tested by simple sensor fabrication .It was observed that the nanorods were initially coalesce in bundles before breaking up loosely towards the end of the hydrothermal process. A response measurement reveals that the sensor was able to detect CO2 at room temperature with the sensitivity around 13ohm/100 ppm. The detection performance of such nanostructure provides a positive indication that it can be a competitive sensor element candidate not only for CO2 applications in particular but can be expanded to other gas sensing application such as O2, C2H4 and NO2.

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