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D. R. Rolison - One of the best experts on this subject based on the ideXlab platform.
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carbon Nanofoam paper enables high rate and high capacity na ion storage
Energy Storage Materials, 2019Co-Authors: Ryan H Deblock, Megan B. Sassin, D. R. Rolison, Jesse S Ko, Ashley N Hoffmaster, Bruce S Dunn, Jeffrey W. LongAbstract:Abstract Carbon Nanofoams (CNF) fabricated within carbon-fiber paper are investigated as negative electrodes for electrochemical Na-ion storage. In electrolyte-limited half-cell testing vs. sodium metal, these freestanding, ultraporous electrode architectures deliver specific capacity >200 mA h gCNF−1 at a 1C rate and >150 mA h gCNF−1 at 10C. The outstanding charge-storage capacity is a consequence of the high defect concentration inherent to the amorphous carbon Nanofoam, which maximizes a capacitively controlled sodiation mechanism, while the through-connected pore structure of the CNF facilitates high-rate capability. We also compare the electrochemical performance of two pore–solid architectural variants of CNF paper electrodes.
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physical entrainment versus chemical binding carbon Nanofoam metal nanoparticles and the role of thiophene linkers
229th ECS Meeting (May 29 - June 2 2016), 2016Co-Authors: Joseph F Parker, Jean Marie Wallace, Natalie L. Brandell, D. R. RolisonAbstract:High-surface-area mesoporous carbon Nanofoams with pore networks interconnected in 3D are particularly versatile electrodes because the surface of the networked carbon can be modified with energy-storing or catalytic materials. The resulting carbon nanostructured papers are device-ready electrodes decorated with well-dispersed, electron-wired, nanoscale functional materials directly sited in the flow field within the through-connected 3D pore network. We can also pre–modify the carbon paper–supported Nanofoams with thiophene-like "hooks" to anchor pre–formed Au nanoparticles adsorbed from colloidal sols. We characterize these native or thiophenylated carbon architectures before and after adsorbing either 5-nm or 15-nm Au colloids by scanning electron microscopy, X-ray photoelectron spectroscopy, and in terms of their electrochemical activity for ethanol oxidation. With these four sets of structurally related electrodes, we can assess whether the metal nanoparticles chemically bind at heterocyclic sulfur in the carbon walls or if they are physically entrained within the nanometric nooks of the ultraporous carbon Nanofoam paper.
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redesigning air cathodes for metal air batteries using mnox functionalized carbon Nanofoam architectures
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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Redesigning air cathodes for metal–air batteries using MnOx-functionalized carbon Nanofoam architectures☆
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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carbon Nanofoam based cathodes for li o2 batteries correlation of pore solid architecture and electrochemical performance
219th ECS Meeting, 2011Co-Authors: Christopher N Chervin, Natalie L. Brandell, Jeffrey W. Long, D. R. RolisonAbstract:Freestanding, binder-free carbon Nanofoam papers afford the opportunity to gauge the influence of pore size on the discharge capacity of Li–O2 cells. Four sets of carbon Nanofoam papers were synthesized from resorcinol–formaldehyde sols, with pore size distributions in pyrolyzed forms ranging from mesopores (5–50 nm) to a size regime not represented in the literature for Li-O2 cathodes—small macropores (50–200 nm). The first-cycle discharge capacity in cells containing 0.1 M LiClO4 in dipropylene glycol dimethyl ether tracks the average pore size distribution in the carbon Nanofoam cathode, rather than the specific surface area of the nanoscale carbon network or its total pore volume. The macroporous Nanofoams yield cathode specific capacity of 1000–1250 mA h g−1 at –0.1 mA cm−2 discharge rate, approximately twice that of the mesoporous Nanofoams (∼580–670 mA h g−1), even though the macroporous foams have lower specific surface areas (270 and 375 vs. >400 m2 g−1). The specific capacity of the cathode decreases as the thickness of macroporous carbon Nanofoam paper is increased from 180to 530-μm, which indicates that the interior pore volume is underutilized, particularly with thicker Nanofoams. For the four pore–solid Nanofoam architectures studied, the specific capacity is limited by pore occlusion arising from solid Li2O2 product that is electrogenerated near the outer boundaries of the Nanofoams. © 2013 The Electrochemical Society. [DOI: 10.1149/2.070309jes] All rights reserved.
Jeffrey W. Long - One of the best experts on this subject based on the ideXlab platform.
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carbon Nanofoam paper enables high rate and high capacity na ion storage
Energy Storage Materials, 2019Co-Authors: Ryan H Deblock, Megan B. Sassin, D. R. Rolison, Jesse S Ko, Ashley N Hoffmaster, Bruce S Dunn, Jeffrey W. LongAbstract:Abstract Carbon Nanofoams (CNF) fabricated within carbon-fiber paper are investigated as negative electrodes for electrochemical Na-ion storage. In electrolyte-limited half-cell testing vs. sodium metal, these freestanding, ultraporous electrode architectures deliver specific capacity >200 mA h gCNF−1 at a 1C rate and >150 mA h gCNF−1 at 10C. The outstanding charge-storage capacity is a consequence of the high defect concentration inherent to the amorphous carbon Nanofoam, which maximizes a capacitively controlled sodiation mechanism, while the through-connected pore structure of the CNF facilitates high-rate capability. We also compare the electrochemical performance of two pore–solid architectural variants of CNF paper electrodes.
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Extending Electrochemical Quartz Crystal Microbalance Techniques to Macroscale Electrodes: Insights on Pseudocapacitance Mechanisms in MnOx-Coated Carbon Nanofoams
Journal of The Electrochemical Society, 2015Co-Authors: Christopher A. Beasley, Megan B. Sassin, Jeffrey W. LongAbstract:ElectrochemicalquartzcrystalmicrobalancestudiesofMnOx-coatedcarbonNanofoamsrevealthatcharge-compensationmechanisms associated with MnOx pseudocapacitance in mild aqueous electrolytes are dominated by anion insertion rather than more commonly reported cation ejection. Specific charge-compensation behavior depends on such factors as electrolyte composition, Nanofoam pore size, andpolarizationamplitude.Forexample,MnOx‐carbonNanofoamswithaverageporesizes of5‐20nm,cycledin2.5MLiNO3, reveal a kinetically-hindered, mixed anion-cation charge-compensation mechanism, whereas the same Nanofoam cycled in 2.5 M NaNO3 shows only anion association. Nanofoams with larger pores (10‐200 nm) that are cycled in 2.5 M LiNO3, reveal anion-only charge compensation. Our results demonstrate that critical new insights on charge-storage mechanisms are achieved using EQCM methods, even when analyzing practical, macroscale electrodes such as carbon Nanofoams. © The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons
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redesigning air cathodes for metal air batteries using mnox functionalized carbon Nanofoam architectures
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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Redesigning air cathodes for metal–air batteries using MnOx-functionalized carbon Nanofoam architectures☆
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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carbon Nanofoam based cathodes for li o2 batteries correlation of pore solid architecture and electrochemical performance
219th ECS Meeting, 2011Co-Authors: Christopher N Chervin, Natalie L. Brandell, Jeffrey W. Long, D. R. RolisonAbstract:Freestanding, binder-free carbon Nanofoam papers afford the opportunity to gauge the influence of pore size on the discharge capacity of Li–O2 cells. Four sets of carbon Nanofoam papers were synthesized from resorcinol–formaldehyde sols, with pore size distributions in pyrolyzed forms ranging from mesopores (5–50 nm) to a size regime not represented in the literature for Li-O2 cathodes—small macropores (50–200 nm). The first-cycle discharge capacity in cells containing 0.1 M LiClO4 in dipropylene glycol dimethyl ether tracks the average pore size distribution in the carbon Nanofoam cathode, rather than the specific surface area of the nanoscale carbon network or its total pore volume. The macroporous Nanofoams yield cathode specific capacity of 1000–1250 mA h g−1 at –0.1 mA cm−2 discharge rate, approximately twice that of the mesoporous Nanofoams (∼580–670 mA h g−1), even though the macroporous foams have lower specific surface areas (270 and 375 vs. >400 m2 g−1). The specific capacity of the cathode decreases as the thickness of macroporous carbon Nanofoam paper is increased from 180to 530-μm, which indicates that the interior pore volume is underutilized, particularly with thicker Nanofoams. For the four pore–solid Nanofoam architectures studied, the specific capacity is limited by pore occlusion arising from solid Li2O2 product that is electrogenerated near the outer boundaries of the Nanofoams. © 2013 The Electrochemical Society. [DOI: 10.1149/2.070309jes] All rights reserved.
Natalie L. Brandell - One of the best experts on this subject based on the ideXlab platform.
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physical entrainment versus chemical binding carbon Nanofoam metal nanoparticles and the role of thiophene linkers
229th ECS Meeting (May 29 - June 2 2016), 2016Co-Authors: Joseph F Parker, Jean Marie Wallace, Natalie L. Brandell, D. R. RolisonAbstract:High-surface-area mesoporous carbon Nanofoams with pore networks interconnected in 3D are particularly versatile electrodes because the surface of the networked carbon can be modified with energy-storing or catalytic materials. The resulting carbon nanostructured papers are device-ready electrodes decorated with well-dispersed, electron-wired, nanoscale functional materials directly sited in the flow field within the through-connected 3D pore network. We can also pre–modify the carbon paper–supported Nanofoams with thiophene-like "hooks" to anchor pre–formed Au nanoparticles adsorbed from colloidal sols. We characterize these native or thiophenylated carbon architectures before and after adsorbing either 5-nm or 15-nm Au colloids by scanning electron microscopy, X-ray photoelectron spectroscopy, and in terms of their electrochemical activity for ethanol oxidation. With these four sets of structurally related electrodes, we can assess whether the metal nanoparticles chemically bind at heterocyclic sulfur in the carbon walls or if they are physically entrained within the nanometric nooks of the ultraporous carbon Nanofoam paper.
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redesigning air cathodes for metal air batteries using mnox functionalized carbon Nanofoam architectures
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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Redesigning air cathodes for metal–air batteries using MnOx-functionalized carbon Nanofoam architectures☆
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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carbon Nanofoam based cathodes for li o2 batteries correlation of pore solid architecture and electrochemical performance
219th ECS Meeting, 2011Co-Authors: Christopher N Chervin, Natalie L. Brandell, Jeffrey W. Long, D. R. RolisonAbstract:Freestanding, binder-free carbon Nanofoam papers afford the opportunity to gauge the influence of pore size on the discharge capacity of Li–O2 cells. Four sets of carbon Nanofoam papers were synthesized from resorcinol–formaldehyde sols, with pore size distributions in pyrolyzed forms ranging from mesopores (5–50 nm) to a size regime not represented in the literature for Li-O2 cathodes—small macropores (50–200 nm). The first-cycle discharge capacity in cells containing 0.1 M LiClO4 in dipropylene glycol dimethyl ether tracks the average pore size distribution in the carbon Nanofoam cathode, rather than the specific surface area of the nanoscale carbon network or its total pore volume. The macroporous Nanofoams yield cathode specific capacity of 1000–1250 mA h g−1 at –0.1 mA cm−2 discharge rate, approximately twice that of the mesoporous Nanofoams (∼580–670 mA h g−1), even though the macroporous foams have lower specific surface areas (270 and 375 vs. >400 m2 g−1). The specific capacity of the cathode decreases as the thickness of macroporous carbon Nanofoam paper is increased from 180to 530-μm, which indicates that the interior pore volume is underutilized, particularly with thicker Nanofoams. For the four pore–solid Nanofoam architectures studied, the specific capacity is limited by pore occlusion arising from solid Li2O2 product that is electrogenerated near the outer boundaries of the Nanofoams. © 2013 The Electrochemical Society. [DOI: 10.1149/2.070309jes] All rights reserved.
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the right kind of interior for multifunctional electrode architectures carbon Nanofoam papers with aperiodic submicrometre pore networks interconnected in 3d
Energy and Environmental Science, 2011Co-Authors: Jean Marie Wallace, Megan B. Sassin, Amanda J. Barrow, Jennifer L. Dysart, Christopher H. Renninger, Matthew P. Saunders, Justin C. Lytle, Jeffrey W. Long, Natalie L. BrandellAbstract:Carbon nanoarchitectures are versatile platforms for advanced electrode structures in which the carbon edifice serves multiple simultaneous functions: a massively parallel 3-D current collector with an interpenetrating structural flow field that facilitates the efficient transport of electrons, ions, and molecules throughout the structure for further functionalization or high-performance electrochemical operation. We fabricate carbon Nanofoam papers by infiltrating commercially available low-density carbon fiber papers with phenolic resin. The polymer-filled paper is ambiently dried and then pyrolyzed to create lightweight, mechanically flexible, and electronically conductive sheets of ultraporous carbon with an electronic conductivity characteristic of the paper support (20–200 S cm−1) rather than RF-derived carbon (typically 0.1–1 S cm−1). The resulting composites comprise nanoscopic carbon walls that are co-continuous with an aperiodic, 3-D interconnected network of mesopores (2 to 50 nm) and macropores (50 nm to 2 µm). Macropores sized at 100–300 nm have not been adequately explored in the literature and offer ample headspace to modify internal carbon walls, thereby introducing new functionality without occluding the interconnected void volume of the Nanofoam. Increasing the viscosity of the polymer sol and matching the surface energetics of the carbon fibers and aqueous sol is necessary to avoid forming a standard carbon aerogel pore–solid structure, where the pores are sized in the micropore (<2 nm) and mesopore range. Carbon Nanofoam papers can be scaled in x, y, and z and are device-ready electrode structures that do not require conductive additives or polymeric binders for electrode fabrication. This one class of Nanofoams serves as a high-surface-area scaffold that can be segued by appropriate modification into multifunctional nanoarchitectures that improve the performance of electrochemical capacitors, lithium-ion batteries, metal–air batteries, fuel cells, and ultrafiltration.
Jean Marie Wallace - One of the best experts on this subject based on the ideXlab platform.
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physical entrainment versus chemical binding carbon Nanofoam metal nanoparticles and the role of thiophene linkers
229th ECS Meeting (May 29 - June 2 2016), 2016Co-Authors: Joseph F Parker, Jean Marie Wallace, Natalie L. Brandell, D. R. RolisonAbstract:High-surface-area mesoporous carbon Nanofoams with pore networks interconnected in 3D are particularly versatile electrodes because the surface of the networked carbon can be modified with energy-storing or catalytic materials. The resulting carbon nanostructured papers are device-ready electrodes decorated with well-dispersed, electron-wired, nanoscale functional materials directly sited in the flow field within the through-connected 3D pore network. We can also pre–modify the carbon paper–supported Nanofoams with thiophene-like "hooks" to anchor pre–formed Au nanoparticles adsorbed from colloidal sols. We characterize these native or thiophenylated carbon architectures before and after adsorbing either 5-nm or 15-nm Au colloids by scanning electron microscopy, X-ray photoelectron spectroscopy, and in terms of their electrochemical activity for ethanol oxidation. With these four sets of structurally related electrodes, we can assess whether the metal nanoparticles chemically bind at heterocyclic sulfur in the carbon walls or if they are physically entrained within the nanometric nooks of the ultraporous carbon Nanofoam paper.
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Redesigning air cathodes for metal–air batteries using MnOx-functionalized carbon Nanofoam architectures☆
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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redesigning air cathodes for metal air batteries using mnox functionalized carbon Nanofoam architectures
Journal of Power Sources, 2012Co-Authors: Christopher N Chervin, Jean Marie Wallace, Natalie L. Brandell, Jeffrey W. Long, Nathan W Kucko, D. R. RolisonAbstract:a b s t r a c t We have redesigned the air cathode for metal–air batteries by adapting fiber-paper-supported carbon Nanofoams as the base electrode architecture. Electrocatalytic functionality for the oxygen reduction reaction (ORR) is added into the conductive, ultraporous Nanofoam paper by electroless deposition at the carbon walls of conformal nanoscopic coatings of birnessite-like manganese oxide (10–20-nm thick MnOx) via redox reaction with aqueous permanganate (MnO4 −). We report the ORR activity measured using an air-breathing electroanalytical cell for a series of native and MnOx-functionalized carbon Nanofoams in which the size of the pore network is varied from tens to hundreds of nanometers, the thickness of the air cathode is varied, and the degree of hydrophilicity/hydrophobicity of the electrode structure is altered. Technologically relevant ORR activity is obtained at 0.9 V vs. Zn for MnOx-functionalized carbon Nanofoams that are ≥180-m thick, have pores on the order of 100–200 nm, and are modified with hydrophobic poly(vinylidene difluoride). © 2012 Elsevier B.V. All rights reserved.
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the right kind of interior for multifunctional electrode architectures carbon Nanofoam papers with aperiodic submicrometre pore networks interconnected in 3d
Energy and Environmental Science, 2011Co-Authors: Jean Marie Wallace, Megan B. Sassin, Amanda J. Barrow, Jennifer L. Dysart, Christopher H. Renninger, Matthew P. Saunders, Justin C. Lytle, Jeffrey W. Long, Natalie L. BrandellAbstract:Carbon nanoarchitectures are versatile platforms for advanced electrode structures in which the carbon edifice serves multiple simultaneous functions: a massively parallel 3-D current collector with an interpenetrating structural flow field that facilitates the efficient transport of electrons, ions, and molecules throughout the structure for further functionalization or high-performance electrochemical operation. We fabricate carbon Nanofoam papers by infiltrating commercially available low-density carbon fiber papers with phenolic resin. The polymer-filled paper is ambiently dried and then pyrolyzed to create lightweight, mechanically flexible, and electronically conductive sheets of ultraporous carbon with an electronic conductivity characteristic of the paper support (20–200 S cm−1) rather than RF-derived carbon (typically 0.1–1 S cm−1). The resulting composites comprise nanoscopic carbon walls that are co-continuous with an aperiodic, 3-D interconnected network of mesopores (2 to 50 nm) and macropores (50 nm to 2 µm). Macropores sized at 100–300 nm have not been adequately explored in the literature and offer ample headspace to modify internal carbon walls, thereby introducing new functionality without occluding the interconnected void volume of the Nanofoam. Increasing the viscosity of the polymer sol and matching the surface energetics of the carbon fibers and aqueous sol is necessary to avoid forming a standard carbon aerogel pore–solid structure, where the pores are sized in the micropore (<2 nm) and mesopore range. Carbon Nanofoam papers can be scaled in x, y, and z and are device-ready electrode structures that do not require conductive additives or polymeric binders for electrode fabrication. This one class of Nanofoams serves as a high-surface-area scaffold that can be segued by appropriate modification into multifunctional nanoarchitectures that improve the performance of electrochemical capacitors, lithium-ion batteries, metal–air batteries, fuel cells, and ultrafiltration.
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The right kind of interior for multifunctional electrode architectures: carbon Nanofoam papers with aperiodic submicrometre pore networks interconnected in 3D
Energy & Environmental Science, 2011Co-Authors: Justin C. Lytle, Jean Marie Wallace, Megan B. Sassin, Amanda J. Barrow, Jennifer L. Dysart, Christopher H. Renninger, Matthew P. Saunders, Natalie L. Brandell, Jeffrey W. Long, D. R. RolisonAbstract:Carbon nanoarchitectures are versatile platforms for advanced electrode structures in which the carbon edifice serves multiple simultaneous functions: a massively parallel 3-D current collector with an interpenetrating structural flow field that facilitates the efficient transport of electrons, ions, and molecules throughout the structure for further functionalization or high-performance electrochemical operation. We fabricate carbon Nanofoam papers by infiltrating commercially available low-density carbon fiber papers with phenolic resin. The polymer-filled paper is ambiently dried and then pyrolyzed to create lightweight, mechanically flexible, and electronically conductive sheets of ultraporous carbon with an electronic conductivity characteristic of the paper support (20-200 S cm-1) rather than RF-derived carbon (typically 0.1-1 S cm-1). The resulting composites comprise nanoscopic carbon walls that are co-continuous with an aperiodic, 3-D interconnected network of mesopores (2 to 50 nm) and macropores (50 nm to 2 [small micro]m). Macropores sized at 100-300 nm have not been adequately explored in the literature and offer ample headspace to modify internal carbon walls, thereby introducing new functionality without occluding the interconnected void volume of the Nanofoam. Increasing the viscosity of the polymer sol and matching the surface energetics of the carbon fibers and aqueous sol is necessary to avoid forming a standard carbon aerogel pore-solid structure, where the pores are sized in the micropore (
R W Eason - One of the best experts on this subject based on the ideXlab platform.
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patterned Nanofoam fabrication from a variety of materials via femtosecond laser pulses
Materials Sciences and Applications, 2019Co-Authors: James A Grantjacob, R W Eason, Benita S Mackay, James Baker, Michael D T Mcdonnell, M Praeger, B MillsAbstract:High-repetition-rate femtosecond lasers enable the precise production of Nanofoam from a wide range of materials. Here, the laser-based fabrication of Nanofoam from silicon, borosilicate glass, sodalime glass, gallium lanthanum sulphide and lithium niobate is demonstrated, where the pore size of the Nanofoam is shown to depend strongly on the material used, such that the pore width and nanofibre width appear to increase with density and thermal expansion coefficient of the material. In addition, the patterning of Nanofoam on a glass slide, with fabricated pattern pixel resolution of ~35 μm, is demonstrated.
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precision manufacturing of laser fabricated Nanofoam
2018Co-Authors: James A Grantjacob, R W Eason, Daniel J Heath, B MillsAbstract:Femtosecond laser machining enables light-matter interactions that may not be possible for nanosecond and longer pulses. Presented here is a method for the targeted fabrication of Nanofoam via 250kHz repetition rate, 4µJ femtosecond pulses.
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laser based fabrication of Nanofoam inside a hollow capillary
Materials Sciences and Applications, 2017Co-Authors: Alexander F Courtier, James A Grantjacob, R W Eason, Daniel J Heath, Rand Ismaeel, Gilberto Brambilla, William J Stewart, B MillsAbstract:Highly porous Nanofoam can be fabricated via multiphoton ablation of a material by raster-scanning femtosecond laser pulses over the material surface. Here, we show the fabrication of Nanofoam on the inside surface of a hollow silica capillary that has an inner and outer diameter of 640 and 700 μm respectively. A thin layer of Nanofoam was fabricated over ~70% of the inner surface of the capillary. Ray-tracing simulations were used to determine the positional corrections required to account for refraction on the curved surface and also to explain the inability to fabricate Nanofoam on the side walls of the capillary.
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laser fabricated Nanofoam from polymeric substrates
2017Co-Authors: B Mills, James A Grantjacob, Daniel J Heath, R W EasonAbstract:Nanofoams are generally defined as a class of nanostructured porous materials with 1µm) size scales.[1] J.A.Grant-Jacob, B.Mills, R.W.Eason, “Parametric study of the rapid fabrication of glass Nanofoam via femtosecond laser irradiation”, Journal of Physics D: Applied Physics 2014 Vol.47(5)pp.055105
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investigation of the rapid fabrication of multiple Nanofoam materials via femtosecond laser irradiation
2014Co-Authors: James A Grantjacob, B Mills, R W EasonAbstract:Nanofoams are permeable, nanostructured materials, which have applications in many areas, including electronics, biological sciences and aerospace engineering [1-4]. Nanofoam fabrication using an ultrafast laser enables control over the precise location as well as the fabrication rate, leading to the possibility of applications such as evanescent sensors and energy harvesting devices. Here, we extend our initial work on glass Nanofoam fabrication [5] by demonstrating the production of metal, ceramic, polymer and novel chalcogenide glass Nanofoam at atmospheric pressure, with dimensions of ~hundred microns in height and millimetre-square in area. Our investigation showed that both the volume and density of the Nanofoam was a function of both the material as well as the exposure protocol (number of pulses and their energy density).
