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2015

Carbon

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Articles 1 - 30 of 48

Full-Text Articles in Engineering

Applications Of Carbon Materials In Electrochemical Energy Storage, Ji Liang, Lei Wen, Hui-Ming Cheng, Feng Li Dec 2015

Applications Of Carbon Materials In Electrochemical Energy Storage, Ji Liang, Lei Wen, Hui-Ming Cheng, Feng Li

Journal of Electrochemistry

An electrode material for electrochemical energy storage is one of the key components for high performance devices. In a variety of electrochemical energy storage systems, carbon materials, especially the lately emerged carbon nanomaterials including the carbon nanotube and graphene, have been playing a very important role and brought new vitality to the development and demonstration of the broad application prospects. In this review, we summarize the applications of various carbon materials in the typical electrochemical energy storage devices, namely lithium/sodium ion batteries, supercapacitors, and lithium-sulfur batteries, as well as flexible electrochemical energy storage and electrochemical catalysis. A perspective of novel …

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Investigation Of Particulate Fume Generated From The Gmaw Of Plain Carbon Steel, Zoran Sterjovski, J Brossier, E De Thoisy, Dominic Cuiuri, John Norrish, Brian Monaghan Dec 2015

Investigation Of Particulate Fume Generated From The Gmaw Of Plain Carbon Steel, Zoran Sterjovski, J Brossier, E De Thoisy, Dominic Cuiuri, John Norrish, Brian Monaghan

Dominic Cuiuri

No abstract provided.

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Tillage System Effects On 15-Year Carbon-Based And Simulated N Budgets In A Tile-Drained Iowa Field, Douglas L. Karlen, Ajay Kumar, Ramesh S. Kanwar, Cynthia A. Cambardella, Thomas S. Colvin Dec 2015

Tillage System Effects On 15-Year Carbon-Based And Simulated N Budgets In A Tile-Drained Iowa Field, Douglas L. Karlen, Ajay Kumar, Ramesh S. Kanwar, Cynthia A. Cambardella, Thomas S. Colvin

Douglas L Karlen

Tillage influences N fate and transport by changing soil structure, aeration, macropore continuity, plant-residue placement, and organic-matter mineralization rates. Our objective was to use 15-year N budgets to compare four primary tillage treatments for continuous corn (Zea mays L.) production on tile-drained Aquic Hapludolls (FAO: Haplic Phaeozems) in northeastern Iowa, USA. A carbon-based N budget used annual grain yield, grain-N concentrations measured in 1992, changes in surface-soil C content between 1977 and 1988 or 1992, surface-soil C : N ratios, and measurements of NO3–N lost in tile-drainage water. It accounted for 98, 104, 99, and 99% of the fertilizer N …

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Carbon Articulating Backpack Spine, Salvatore Monforte Iii, Darci Lawrence, Savan Patel Dec 2015

Carbon Articulating Backpack Spine, Salvatore Monforte Iii, Darci Lawrence, Savan Patel

Mechanical Engineering

In the field, firefighters and Urban Search and Rescue (USAR) personnel need to transport variable loads efficiently, safely, and comfortably while simultaneously performing certain physical tasks. Current models of external and internal framed backpacks distribute the load of a pack efficiently, but do not allow for the natural movement of the wearer. Wolfpack Gear, Inc. proposed the need for a system which both effectively carries a load and allows for the unhindered natural movement of the user. The goal of this project was to design, build, and test an articulating backpack support system. The first stage of the project comprised …

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Size-Controlled Large-Diameter And Few-Walled Carbon Nanotube Catalysts For Oxygen Reduction, Xianliang Wang, Qing Li, Hengyu Pan, Ye Lin, Yujie Ke, Haiyang Sheng, Mark T. Swihart, Gang Wu Nov 2015

Size-Controlled Large-Diameter And Few-Walled Carbon Nanotube Catalysts For Oxygen Reduction, Xianliang Wang, Qing Li, Hengyu Pan, Ye Lin, Yujie Ke, Haiyang Sheng, Mark T. Swihart, Gang Wu

Faculty Publications

We demonstrate a new strategy for tuning the size of large-diameter and few-walled nitrogen-doped carbon nanotubes (N-CNTs) from 50 to 150 nm by varying the transition metal (TM = Fe, Co, Ni or Mn) used to catalyze graphitization of dicyandiamide. Fe yielded the largest tubes, followed by Co and Ni, while Mn produced a clot-like carbon morphology. We show that morphology is correlated with electrocatalytic activity for the oxygen reduction reaction (ORR). A clear trend of Fe > Co > Ni > Mn for the ORR catalytic activity was observed, in both alkaline media and more demanding acidic media. The Fe-derived N-CNTs exhibited …

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Nanostructured Carbon Materials For Active And Durable Electrocatalysts And Supports In Fuel Cells, Adam Riese Sep 2015

Nanostructured Carbon Materials For Active And Durable Electrocatalysts And Supports In Fuel Cells, Adam Riese

Electronic Thesis and Dissertation Repository

Meeting the energy demands of the future will require a breadth of technologies and materials for generating and converting electricity. Increasing activity and reducing costs of electrocatalysts for fuel cells is among the most important challenges for the technology. With advances in nanomaterials there has been increased interest in creating novel catalysts with both high activity and excellent long-term durability. This thesis aims to understand how modification of nanostructured carbons can be used to improve the activity and durability of catalysts and supports for the oxygen reduction reaction (ORR). Using an integrating approach to synthesis, characterization, and electrochemical testing, it …

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Enhancement Of Removal Of Trace Organic Contaminants By Powdered Activated Carbon Dosing Into Membrane Bioreactors, Ngoc Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price, Chul Park, Kazuo Yamamoto Sep 2015

Enhancement Of Removal Of Trace Organic Contaminants By Powdered Activated Carbon Dosing Into Membrane Bioreactors, Ngoc Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price, Chul Park, Kazuo Yamamoto

Faisal I Hai

This study compared the removal efficiency of 22 widespread trace organic contaminants by a laboratory-scale membrane bioreactor (MBR) with and without direct addition of powdered activated carbon (PAC) into the activated sludge reactor over a period of 312 days. The removal of hydrophilic and biologically persistent trace organic contaminants was immediately improved to above 95% after the addition of PAC into MBR. However, a compound-specific gradual decrease in removal underscored the requirement for the addition of fresh PAC. Adsorption onto PAC-added sludge appeared to play a significant role in the relatively more effective aqueous phase removal of a few resistant …

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Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung Sep 2015

Comparison Between Sequential And Simultaneous Application Of Activated Carbon With Membrane Bioreactor For Trace Organic Contaminant Removal, Luong N. Nguyen, Faisal I. Hai, Jinguo Kang, Long D. Nghiem, William E. Price, Wenshan Guo, Huu H. Ngo, Kuo-Lun Tung

Faisal I Hai

The removal efficiency of 22 selected trace organic contaminants by sequential application of granular activated carbon (GAC) and simultaneous application of powdered activated carbon (PAC) with membrane bioreactor (MBR) was compared in this study. Both sequential application of GAC following MBR treatment (MBR–GAC) and simultaneous application of PAC within MBR (PAC–MBR) achieved improved removal (over 95%) of seven hydrophilic and biologically persistent compounds, which were less efficiently removed by MBR-only treatment (negligible to 70%). However, gradual breakthrough of these compounds occurred over an extended operation period. Charged compounds, particularly, fenoprop and diclofenac, demonstrated the fastest breakthrough (complete and 50–70%, in …

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Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem Sep 2015

Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem

Faisal I Hai

This study investigated the removal of trace organic contaminants by a combined membrane bioreactor - granular activated carbon (MBR-GAC) system over a period of 196 days. Of the 22 compounds investigated here, all six hydrophilic compounds with electron-withdrawing functional groups (i.e., metronidazole, carbamazepine, ketoprofen, naproxen, fenoprop and diclofenac) exhibited very low removal efficiency by MBR-only treatment. GAC post-treatment initially complemented MBR treatment very well; however, a compound-specific gradual deterioration of the removal of the above-mentioned problematic compounds was noted. While a 20% breakthrough of all four negatively charged compounds namely ketoprofen, naproxen, fenoprop and diclofenac occurred within 1000-3000 bed volumes …

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Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price Sep 2015

Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price

Faisal I Hai

the occurrence of trace organics such as pesticides, pharmaceutically active compounds, natural and synthetic hormones as well as varous industrial compounds in the aquatic environment is of great concern due to their potential adverse effects on human health and those of other biota. Therefore, the removal of these compounds from wastewater is an important consideration to ensure safe drinking water and better protection of the environment. In the literature, several techniques have been explored for trace organics removal, namely, conventional activated sludge, membrane bioreactors (MBRs), and absorptioin. However it has been found that neither MBR nor activated carbon on its …

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Estimates Of Biomass And Fixed Carbon At A Rainforest In Panama, Reinhardt Pinzón, José Fábrega, David Vega, Erick N. Vallester, Rafael Aizprúa, Francisco R. López-Serrano, Fred Ogden, Kleveer Espino Jun 2015

Estimates Of Biomass And Fixed Carbon At A Rainforest In Panama, Reinhardt Pinzón, José Fábrega, David Vega, Erick N. Vallester, Rafael Aizprúa, Francisco R. López-Serrano, Fred Ogden, Kleveer Espino

Fred L. Ogden

This paper presents an estimation of the quantity of carbon fixed in trees in a one hectare (ha) plot at the Cerro Pelado-Gamboa Hydrology Tropical Observatory, which is located in the province of Colon, Panama. The estimation of carbon fixed in trees may provide significant information on carbon flux due to water circulation, which may ultimately enable evaluation of the carbon cycle. All trees larger than 10 cm diameter at breast height (DBH) in the plot were investigated. Carbon fixed within these trees was estimated using a parameterized formula. Tree biomass estimations for the plot were 97.21 Mg ha -1. …

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Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace Jun 2015

Capacitive Behavior Of Latex/Single-Wall Carbon Nanotube Stretchable Electrodes, Hyeon Taek Jeong, Byung Kim, Robert Gorkin Iii, Michael J. Higgins, Gordon G. Wallace

Robert Gorkin III

In this report single-wall carbon nanotubes (SWNTs) were coated onto latex using spray coating to produce a stretchable electrode. The electrochemical properties of the electrode were determined using cyclic voltammetry and electrochemical impedance spectroscopy and galvanostatic charge/discharge tests were also carried out. The impedance and charge/discharge curves of the latex/SWNTs electrode showed good capacitive behavior even after repetitive stretching to 100% strain. The highest capacitance value obtained for the unstretched SWNTs electrode was 119 F g−1 in 1 M Na2SO4 at 5 mV s−1. After the 100th stretch ≈ 80% of the original capacitance value was retained.

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Carbon Fiber Monocoque Development For A Formula Sae Racecar, Andrew Cunningham, Andrew Ferrell, Matthew Lee, Tony Loogman Jun 2015

Carbon Fiber Monocoque Development For A Formula Sae Racecar, Andrew Cunningham, Andrew Ferrell, Matthew Lee, Tony Loogman

Mechanical Engineering

Monocoque development of the 2015 Cal Poly Formula SAE racecar from design to competition.

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Kinetic Modeling Of Catalytic Aerogels, Yi Cao Jun 2015

Kinetic Modeling Of Catalytic Aerogels, Yi Cao

Honors Theses

As pollution becomes an increasing concern globally, strict regulations have been set on vehicle pollutant emissions. The three-way catalytic converter is capable of converting toxic emissions such as carbon monoxide, unburned hydrocarbons and nitrogen oxides to less hazardous waste such as carbon dioxide, water, and nitrogen. Current catalysts employ platinum group metals, which are expensive and environmentally damaging to mine. Catalytically-active aerogels such as Co-Al, Cu-Al and V-Al aerogels have shown promise as alternatives to these metals. The work presented here adapts and extends a global kinetic model which predicts the conversion of hydrocarbons and carbon monoxide on platinum catalyst …

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Isotope-Based Fluvial Organic Carbon (Isofloc) Model: Model Formulation, Sensitivity, And Evaluation, William I. Ford, James F. Fox Jun 2015

Isotope-Based Fluvial Organic Carbon (Isofloc) Model: Model Formulation, Sensitivity, And Evaluation, William I. Ford, James F. Fox

Civil Engineering Faculty Publications

Watershed-scale carbon budgets remain poorly understood, in part due to inadequate simulation tools to assess in-stream carbon fate and transport. A new numerical model termed ISOtope-based FLuvial Organic Carbon (ISOFLOC) is formulated to simulate the fluvial organic carbon budget in watersheds where hydrologic, sediment transport, and biogeochemical processes are coupled to control benthic and transported carbon composition and flux. One ISOFLOC innovation is the formulation of new stable carbon isotope model subroutines that include isotope fractionation processes in order to estimate carbon isotope source, fate, and transport. A second innovation is the coupling of …

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Inter-Laboratory Variation In The Chemical Analysis Of Acidic Forest Soil Reference Samples From Eastern North America, D. S. Ross, S. W. Bailey, R. D. Briggs, J. Curry, I. J. Fernandez, G. Fredriksen, C. L. Goodale, P. W. Hazlett, P. R. Heine, C. E. Johnson, J. T. Larson, G. B. Lawrence, R. K. Kolka, R. Ouimet, D. Paré, D. De B. Richter, C. D. Schirmer, R. A. Warby May 2015

Inter-Laboratory Variation In The Chemical Analysis Of Acidic Forest Soil Reference Samples From Eastern North America, D. S. Ross, S. W. Bailey, R. D. Briggs, J. Curry, I. J. Fernandez, G. Fredriksen, C. L. Goodale, P. W. Hazlett, P. R. Heine, C. E. Johnson, J. T. Larson, G. B. Lawrence, R. K. Kolka, R. Ouimet, D. Paré, D. De B. Richter, C. D. Schirmer, R. A. Warby

Civil and Environmental Engineering

Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from agronomic and horticultural soils. Soil proficiency programs do not generally include forest soil samples that are highly acidic, high in extractable Al, low in extractable Ca and often high in carbon. To determine the uncertainty associated with specific analytical methods for forest soils, we collected and distributed samples from two …

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The Use Of Cod, Toc, Fluorescence, And Absorbance Spectroscopy To Estimate Biochemical Oxygen Demand In Wastewater, Evelyn Aramaine Christian May 2015

The Use Of Cod, Toc, Fluorescence, And Absorbance Spectroscopy To Estimate Biochemical Oxygen Demand In Wastewater, Evelyn Aramaine Christian

UNLV Theses, Dissertations, Professional Papers, and Capstones

All wastewater treatment facilities must obtain a National Pollution Discharge Elimination System (NPDES) permit, which regulates the quality of water that is discharged. Common to all NPDES permits is a limit on organic matter, as determined by the five-day biochemical oxygen demand (BOD5) test. More rapid methods, such as chemical oxygen demand (COD), total organic carbon (TOC), fluorescence, and absorbance spectroscopy are also capable of quantifying organic matter. Previous studies indicate it is possible to develop correlations between these parameters. This study explored the correlations using influent, primary clarifier effluent, and finished effluent samples from an operational wastewater treatment plant …

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Stitch Fiber Comparison For Improvement Of Interlaminar Fracture Toughness In Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori Apr 2015

Stitch Fiber Comparison For Improvement Of Interlaminar Fracture Toughness In Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori

Dr. Kwek-Tze Tan

In this study, strain energy release rates are measured and compared for laminated composites reinforced by through-thickness stitching using different stitch fiber materials — Carbon, Kevlar, and Vectran. Strain energy release rates are evaluated experimentally using the DCB test and validated computationally using FEA. The FE model of the stitched composite incorporates a novel four-step stitch fracture process, namely: interfacial debonding, slack absorption, fiber breakage, and pull-out friction. The FE predictions of GIC show good agreement with the experimental results. It is revealed that the relationship between G IC and stitch density, or stitch thread volume fraction for all …

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An Evaluation Of Carbon Concentrations Associated With Biodiesel Particulate Matter In An Underground Metal Mine, David Evans Apr 2015

An Evaluation Of Carbon Concentrations Associated With Biodiesel Particulate Matter In An Underground Metal Mine, David Evans

Graduate Theses & Non-Theses

Exposure to diesel particulate matter from diesel exhaust has been shown to have adverse health effects in humans. In 2012 The International Agency for Research on Cancer classified diesel exhaust as a group 1 know human carcinogen. Because of the associated health effects, there has been a strong push to reduce the amount of diesel exhaust present in the mining industry. Biodiesel is one to the more common and promising control options used to reduce the amount of diesel particulate matter that is generated during fuel combustion. The use of biodiesel over petroleum diesel has been shown to reduce not …

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Modeling Lithium Intercalation In A Porous Carbon Electrode, Gerardine G. Botte, Ralph E. White Mar 2015

Modeling Lithium Intercalation In A Porous Carbon Electrode, Gerardine G. Botte, Ralph E. White

Ralph E. White

No abstract provided.

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Elimination Of Hydrogenase Active Site Assembly Blocks H2 Production And Increases Ethanol Yield In Clostridium Thermocellum, Ranjita Biswas, Tianyong Zheng, Daniel G. Olson, Lee R. Lynd, Adam M. Guss Feb 2015

Elimination Of Hydrogenase Active Site Assembly Blocks H2 Production And Increases Ethanol Yield In Clostridium Thermocellum, Ranjita Biswas, Tianyong Zheng, Daniel G. Olson, Lee R. Lynd, Adam M. Guss

Dartmouth Scholarship

Background: The native ability of Clostridium thermocellum to rapidly consume cellulose and produce ethanol makes it a leading candidate for a consolidated bioprocessing (CBP) biofuel production strategy. C. thermocellum also synthesizes lactate, formate, acetate, H2 , and amino acids that compete with ethanol production for carbon and electrons. Elimination of H2 production could redirect carbon flux towards ethanol production by making more electrons available for acetyl coenzyme A reduction to ethanol. Results: H2 production in C. thermocellum is encoded by four hydrogenases. Rather than delete each individually, we targeted hydrogenase maturase gene hydG, involved in converting the …

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Assessment Of Ghg Emission Reduction Potential From Source-Separated Organic Waste (Sow) Management: Case Study In A Higher Educational Institution In Malaysia Feb 2015

Assessment Of Ghg Emission Reduction Potential From Source-Separated Organic Waste (Sow) Management: Case Study In A Higher Educational Institution In Malaysia

Faculty of Engineering University of Malaya

In Malaysia, the greenhouse gases (GHGs) emissions reduction via composting of source-separated organic waste (SOW) in municipal solid waste (MSW) has not been assessed. Assessment of GHG emissions reduction via composting of SOW is important as environmental impacts from waste management are waste-specific and local-specific. The study presents the case study for potential carbon reduction via composting of SOW in University of Malaya (UM). In this study, a series of calculations were used to evaluate the GHG emission of different SOW management scenarios. The calculations based on IPCC calculation methods (AM0025) include GHGs emissions from landfilling, fuel consumption in transportation …

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Contaminant-Tolerant Solvent And Stripping Chemical And Process For Using Same For Carbon Capture From Combustion Gases, Kunlei Liu, James K. Neathery, Joseph E. Remias Jan 2015

Contaminant-Tolerant Solvent And Stripping Chemical And Process For Using Same For Carbon Capture From Combustion Gases, Kunlei Liu, James K. Neathery, Joseph E. Remias

Center for Applied Energy Research Faculty Patents

A contaminant-tolerant hybrid scrubbing solvent is provided for post-combustion CO2 capture and removal, the scrubbing solvent including an amine and a low fraction of ammonia. A stripping carrier having a low latent energy is included for solvent regeneration. In one embodiment, the amine is MEA and the stripping chemical having low latent energy is pentane or an isomer thereof. Processes and apparatus for CO2 removal from post-combustion gases and for solvent regeneration are described.

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Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden Jan 2015

Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden

Dissertations, Master's Theses and Master's Reports - Open

The thermoset epoxy resin EPON 862, coupled with the DETDA hardening agent, are utilized as the polymer matrix component in many graphite (carbon fiber) composites. Because it is difficult to experimentally characterize the interfacial region, computational molecular modeling is a necessary tool for understanding the influence of the interfacial molecular structure on bulk-level material properties. The purpose of this research is to investigate the many possible variables that may influence the interfacial structure and the effect they will have on the mechanical behavior of the bulk level composite. Molecular models are established for EPON 862-DETDA polymer in the presence of …

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Stretchable, Weavable Coiled Carbon Nanotube/Mno2/Polymer Fiber Solid-State Supercapacitors, Changsoon Choi, Shi Hyeong Kim, Hyeon Jun Sim, Jae Ah Lee, A Young Choi, Youn Tae Kim, Xavier Lepro, Geoffrey M. Spinks, Ray H. Baughman, Seon Jeong Kim Jan 2015

Stretchable, Weavable Coiled Carbon Nanotube/Mno2/Polymer Fiber Solid-State Supercapacitors, Changsoon Choi, Shi Hyeong Kim, Hyeon Jun Sim, Jae Ah Lee, A Young Choi, Youn Tae Kim, Xavier Lepro, Geoffrey M. Spinks, Ray H. Baughman, Seon Jeong Kim

Australian Institute for Innovative Materials - Papers

Fiber and yarn supercapacitors that are elastomerically deformable without performance loss are sought for such applications as power sources for wearable electronics, micro-devices, and implantable medical devices. Previously reported yarn and fiber supercapacitors are expensive to fabricate, difficult to upscale, or non-stretchable, which limits possible use. The elastomeric electrodes of the present solid-state supercapacitors are made by using giant inserted twist to coil a nylon sewing thread that is helically wrapped with a carbon nanotube sheet, and then electrochemically depositing pseudocapacitive MnO2 nanofibers. These solid-state supercapacitors decrease capacitance by less than 15% when reversibly stretched by 150% in the …

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Contribution Of Radicals And Ions In Catalyzed Growth Of Single-Walled Carbon Nanotubes From Low-Temperature Plasmas, Z Marvi, S Xu, G Foroutan, Kostya Ostrikov Jan 2015

Contribution Of Radicals And Ions In Catalyzed Growth Of Single-Walled Carbon Nanotubes From Low-Temperature Plasmas, Z Marvi, S Xu, G Foroutan, Kostya Ostrikov

Australian Institute for Innovative Materials - Papers

The growth kinetics of single-walled carbon nanotubes (SWCNTs) in a low-temperature, low-pressure reactive plasma is investigated using a multiscale numerical simulation, including the plasma sheath and surface diffusion modules. The plasma-related effects on the characteristics of SWCNT growth are studied. It is found that in the presence of reactive radicals in addition to energetic ions inside the plasma sheath area, the effective carbon flux, and the growth rate of SWCNT increase. It is shown that the concentration of atomic hydrogen and hydrocarbon radicals in the plasma plays an important role in the SWCNT growth. The effect of the effective carbon …

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Dual Yolk-Shell Structure Of Carbon And Silica-Coated Silicon For High-Performance Lithium-Ion Batteries, L Y. Yang, H Z. Li, Jun Liu, Ziqi Sun, S S. Tang, M Lei Jan 2015

Dual Yolk-Shell Structure Of Carbon And Silica-Coated Silicon For High-Performance Lithium-Ion Batteries, L Y. Yang, H Z. Li, Jun Liu, Ziqi Sun, S S. Tang, M Lei

Australian Institute for Innovative Materials - Papers

Silicon batteries have attracted much attention in recent years due to their high theoretical capacity, although a rapid capacity fade is normally observed, attributed mainly to volume expansion during lithiation. Here, we report for the first time successful synthesis of Si/void/SiO2/void/C nanostructures. The synthesis strategy only involves selective etching of SiO2 in Si/SiO2/C structures with hydrofluoric acid solution. Compared with reported results, such novel structures include a hard SiO2-coated layer, a conductive carbon-coated layer, and two internal void spaces. In the structures, the carbon can enhance conductivity, the SiO2 layer has mechanically …

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Uniform Yolk-Shell Iron Sulfide-Carbon Nanospheres For Superior Sodium-Iron Sulfide Batteries, Yunxiao Wang, Jianping Yang, Shulei Chou, Hua-Kun Liu, Weixian Zhang, Dongyuan Zhao, S X. Dou Jan 2015

Uniform Yolk-Shell Iron Sulfide-Carbon Nanospheres For Superior Sodium-Iron Sulfide Batteries, Yunxiao Wang, Jianping Yang, Shulei Chou, Hua-Kun Liu, Weixian Zhang, Dongyuan Zhao, S X. Dou

Australian Institute for Innovative Materials - Papers

Sodium-metal sulfide battery holds great promise for sustainable and cost-effective applications. Nevertheless, achieving high capacity and cycling stability remains a great challenge. Here, uniform yolk-shell iron sulfide-carbon nanospheres have been synthesized as cathode materials for the emerging sodium sulfide battery to achieve remarkable capacity of ∼545 mA h g-1 over 100 cycles at 0.2 C (100 mA g-1), delivering ultrahigh energy density of ∼438 Wh kg-1. The proven conversion reaction between sodium and iron sulfide results in high capacity but severe volume changes. Nanostructural design, including of nanosized iron sulfide yolks (∼170 nm) with porous carbon shells (∼30 nm) and …

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High Acetic Acid Production Rate Obtained By Microbial Electrosynthesis From Carbon Dioxide, Ludovic Jourdin, Timothy Grieger, Juliette Monetti, Victoria Flexer, Stefano Freguia, Yang Lu, Jun Chen, Mark S. Romano, Gordon G. Wallace, Jurg Keller Jan 2015

High Acetic Acid Production Rate Obtained By Microbial Electrosynthesis From Carbon Dioxide, Ludovic Jourdin, Timothy Grieger, Juliette Monetti, Victoria Flexer, Stefano Freguia, Yang Lu, Jun Chen, Mark S. Romano, Gordon G. Wallace, Jurg Keller

Australian Institute for Innovative Materials - Papers

High product specificity and production rate are regarded as key success parameters for large-scale applicability of a (bio)chemical reaction technology. Here, we report a significant performance enhancement in acetate formation from CO2, reaching comparable productivity levels as in industrial fermentation processes (volumetric production rate and product yield). A biocathode current density of -102 ± 1 A m-2 and an acetic acid production rate of 685 ± 30 (g m-2 day-1) have been achieved in this study. High recoveries of 94 ± 2% of the CO2 supplied as the sole carbon source and 100 ± 4% of electrons into the final …

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One Dimensional Graphitic Carbon Nitrides As Effective Metal-Free Oxygen Reduction Catalysts, Muhammad Nawaz Tahir, Nasir Mahmood, Jinghan Zhu, Asif Mahmood, Faheem K. Butt, Syed Rizwan, Imran Aslam, M Tanveer, Faryal Idrees, Imran Shakir, Chuanbao Cao, Yanglong Hou Jan 2015

One Dimensional Graphitic Carbon Nitrides As Effective Metal-Free Oxygen Reduction Catalysts, Muhammad Nawaz Tahir, Nasir Mahmood, Jinghan Zhu, Asif Mahmood, Faheem K. Butt, Syed Rizwan, Imran Aslam, M Tanveer, Faryal Idrees, Imran Shakir, Chuanbao Cao, Yanglong Hou

Australian Institute for Innovative Materials - Papers

To explore the effect of morphology on catalytic properties of graphitic carbon nitride (GCN), we have studied oxygen reduction reaction (ORR) performance of two different morphologies of GCN in alkaline media. Among both, tubular GCN react with dissolved oxygen in the ORR with an onset potential close to commercial Pt/C. Furthermore, the higher stability and excellent methanol tolerance of tubular GCN compared to Pt/C emphasizes its suitability for fuel cells.

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