John P Ferraris

University of Texas at Dallas | UTD · Chemistry

Carbon molecular sieve membranes (CMSMs) were prepared by carbonizing the high free volume polyimide BTDA-BAF that is obtained from the reaction of benzophenone-3,3′,4,4′-tetracarboxylic dianhydride (BTDA) and 9,9-bis(4-aminophenyl) fluorene (BAF). The bulky cardo groups prevented a tight packing and rotation of the chains that leads to high permea...

Organic–inorganic nanohybrids are widely used in supercapacitor electrode materials. However, the role of the interfaces in nanohybrids is not well understood. Five different types of interfaces and combinations have been described in this chapter. The interaction quotient (IQ), a qualitative measure of the interfacial contact, increases from physi...

Two-dimensional mesoporous hexagonal carbon sheets (MHCSs) have been prepared via a chemical vapor deposition method employing mesoporous Mg(OH) 2 hexagonal sheets as the template and acetylene gas as the carbon precursor. MHCSs with porosity in the micropore−mesopore range have a high specific surface area of 1785 m 2 ·g −1. The hierarchical micro...

Hierarchical porous carbon nanosheet (HPCN) materials of different thicknesses were fabricated on Mg(OH) 2 substrates utilizing a one-step chemical vapor deposition (CVD) approach. The templated carbon nanosheets are closely packed hierarchical nanostructures possessing high surface areas varying from 1323 to 1978 m 2 ·g −1. Symmetrical electrochem...

Hybrid supercapacitors made of carbon - metal oxide composites are devices which combine the advantages of electric double layer capacitors and pseudocapacitors viz. high energy density, high power density and high cyclability. Hybrid supercapacitors made of carbon - metal oxide composites are devices which combine the advantages of electric double...

Current energy demands and technological advancements will require a wide array of energy storage devices such as supercapcitors that can deliver large quantities of energy quickly. Electrochemical double layer capacitors (EDLC) are capable of cycling thousands of times with minimal drop in total capacitance, and when used with an ionic liquid elec...

Hierarchical porous carbons (HPCs) hold great promise in energy-related applications owing to their excellent chemical stability and well-developed porous structures. Attention has been drawn toward developing new synthetic strategies and precursor materials that permit greater control over composition, size, morphology, and pore structure. There i...

A series of aromatic polyimides derived from 4,4’-hexafluoroisopropylidine diphthalic anhydride (6FDA), with different ratios of 2,4,6-trimethyl-1,3-phenylenediamine (DAM), and 3,5-diaminobenzoic acid (DABA) were investigated as carbon precursors for supercapacitors. The synthesized polymers were electrospun and subjected to thermal treatment which...

Hierarchical porous carbons (HPCs) hold great promise in energy-related applications owing to their excellent chemical stability and well-developed porous structures. Attention has been drawn toward developing new synthetic strategies and precursor materials that permit greater control over composition, size, morphology, and pore structure. There i...

An acrylonitrile based co-polymer, poly(acrylonitrile-co-itaconic acid), P(AN-co-IA) was synthesized with different amounts of itaconic acid (IA) to study in situ porogen activity of IA to produce porous carbon nanofibers (CNFs) without any subsequent physical or chemical activation. The concept developed here avoids unnecessary and complex extra a...

Lignin was blended with polyacrylonitrile (PAN) in different ratios and fabricated into carbon nanofiber electrodes by electrospinning followed by thermal stabilization, carbonization and subsequent activation by CO₂ of the carbonized mats. These carbon fiber electrodes exhibit high surface area, high mesoporosity, high graphitic content...

Global demand for alternative energy storage and improved energy infrastructure will require energy storage devices that can store large quantities of energy and deliver them quickly. These devices should do so for thousands upon thousands of cycles. Supercapacitor devices are an attractive method for future energy storage due to their highpower de...

Hybrid supercapacitors made of carbon – metal oxide composites are devices which can combine the advantages of both electric double layer capacitors and pseudocapacitors e.g. high energy density, high power density and high cyclibilty. Although there are many ways to make carbon – metal oxide composites, carbon nanofibers (CNFs) as high surface are...

Carbon nanofibers (CNFs) were fabricated by blending PBI (Polybenzimidazole) and 6FDD (6FDA-DAM-DABA, a copolymer of 4,4-hexafluoroisopropylidene diphthalic anhydride (6FDA), 2,4,6-trimethyl-1,3-phenylenediamine (DAM) and 3,5-diaminobenzoic acid (DABA)). PBI and 6FDD are immiscible polymers comprising PBI as continuous phase and 6FDD as dispersed p...

Immiscible polymer blends yield carbon materials with fine and controlled pore architectures for supercapacitor applications. Aromatic polyimides derived from 4,4’-hexafluoroisopropylidine diphthalic anhydride (6FDA) have attracted attention as high performance polymers due to their high free volume and thermal stability. In this study, 6FDA and DA...

Composite electrodes composed of vanadium pentoxide nanoflowers (VNFs) and carbon nanofibers (CNFs) were prepared by co-electrospinning method. Co-polymer poly(acrylonitrile-co-itaconic acid) was used to provide the carbon backbone. Presence of the itaconic acid allows for in situ activation. Morphological analysis shows that upon carbonization the...

For electrodes in electrochemical double-layer capacitors, carbon nanofibers (CNFs) were prepared by thermal treatment of precursor polymer nanofibers, fabricated by electrospinning. Poly(acrylonitrile-co-vinylimidazole) (PAV) was employed as a precursor polymer of carbon nanofibers due to the effective cyclization of PAV polymer chains during ther...

Although propylene/propane separation remains a challenge for industrial processes, carbon molecular sieve membranes (CMSMs) have the potential to replace traditional separation methods. A high molecular weight crosslinkable polyimide was utilized to fabricate CMSMs, which showed pure gas permeabilities in excess of 400 barrers with propylene/propa...

Flexible, free standing and binder-free electrodes were fabricated by electrospinning from a series of lignin: polyvinyl alcohol (PVA) polymer blends, followed by heat treatment. PVA has the dual function of facilitating the electrospinning of lignin and acting as a sacrificial polymer. Upon stabilization, carbonization and CO2 activation, carbon n...

Capacity degradation by phase changes and oxygen evolution has been the largest obstacle for the ultimate commercialization of high‐capacity LiNiO2‐based cathode materials. The ultimate thermodynamic and kinetic reasons of these limitations are not yet systematically studied, and the fundamental mechanisms are still poorly understood. In this work,...

Lanthanum hydroxide nanorods were employed as both a template and catalyst for carbon synthesis by chemical vapor deposition. The resulting carbon possesses hollow nanorod shapes with graphitic walls. The hollow carbon nanorods were interconnected at some junctions forming a mazelike network, and the broken ends of the tubular carbon provide access...

The Effect of Sample Preparation on Observed Microstructure in Polymeric and Polymer Composite Gas Separation Membranes - Volume 24 Supplement - Charles J. Holt, Kenneth J. Balkus, John P. Ferraris, Inga H. Musselman

Carbon nanofibers (CNFs) are promising electrode materials for electrochemical double layer capacitors (EDLCs) due to their high porosity and electrical conductivity. CNFs were prepared by electrospinning and subsequent thermal treatment of a new precursor polymer, 6FDA-durene, without the addition of pore generating agents. The conversion of precu...

Wrinkled mesoporous silica (WMS) has been shown to be a promising material for catalysis and drug delivery. The WMS possesses a unique wrinkled structure with conical shaped pores radiating from the center to the surface of each particle. Lanthanum oxide was supported on wrinkled mesoporous silica as a hard template for the synthesis of graphitic c...

Carbon nanofibers with high surface area have become promising electrode materials for supercapacitors because of their importance in increasing energy density. In this study, a high free volume polymer, 6FDA-DAM:DABA (6FDD) was blended with polybenzimidazole (PBI) in different ratios to obtain different compositions of PBI/6FDD immiscible polymer...

VTEC™ PI-1388 and 20 wt% (Al) NH2-MIL-53/VTEC™ PI-1388 mixed-matrix membranes (MMMs) with different thicknesses were tested for gas permeation of H2 and CO2 from 5 to 30 bar and from 35 to 300 °C. 50/50 H2/CO2 mixtures were also tested at 30 bar and 250 °C with stage cuts that ranged from 0.05 to 1. Gas permeation data show that the affinity of (Al...

Thermoacoustic performance of thin freestanding sheets of carbonized poly(acrylonitrile) and polybenzimidazole nanofibers are studied as promising candidates for thermophones. We analyze thermodynamic properties of sheets using transport parameters of single nanofibers and their aligned and randomly electrospun thin film assemblies. The electrical...

For the first time, porous organic polymers (POPs) based on the smallest buckybowl, corannulene (BB-POPs) have been synthesized. Three POPs were synthesised via Sonogashira co-polymerization of 1,2,5,6-tetrabromocorannulene and alkyne linkers. BB-POP-3 exhibits the highest surface area (SABET = 560 m(2) g(-1)) and CO2 adsorption of 11.7 wt%, while...

Porous carbon nanofibers were prepared by electrospinning blend solutions of polybenzimidazole/poly-L-lactic acid (PBI/PLLA) and carbonization. During thermal treatment, PLLA was decomposed, resulting in the creation of pores in the carbon nanofibers. From SEM images, it is shown that carbon nanofibers had diameters in the range of 100-200 nm. The...

Gas separation for industrial, energy, and environmental applications requires low energy consumption and small footprint technology to minimize operating and capital costs for the processing of large volumes of gases. Among the separation methods currently being used, like distillation, amine scrubbing, and pressure and temperature swing adsorptio...

Membrane-based gas separation has attracted a great deal of attention recently due to the requirement for high purity gasses in industrial applications like fuel cells, and because of environment concerns, such as global warming. The current methods of cryogenic distillation and pressure swing adsorption are energy intensive and costly. Therefore,...

Thermally sensitive tetramethylammonium oxalate (TMAO) is incorporated as an in situ porogen into freestanding nonwoven nanofibers of polyacrylonitrile (PAN) produced by electrospinning. Supercapacitor electrode materials are prepared by a series of thermal treatments on these fibers, including stabilization followed by a single step carbonization...

An immiscible polymer blend comprising high performance co-polyimide 6FDA-DAM:DABA(3:2) (6FDD) and polybenzimidazole (PBI) was compatibilized using 2-methylimidazole (2-MI), a commercially available small molecule. Membranes were fabricated from blends of 6FDD:PBI (50:50) with and without 2-MI for H2/CO2 separations. The membranes demonstrated a ma...

A novel nanohybrid material composed of vanadium pentoxide nanofibres (VNFs) and exfoliated graphene were prepared by in-situ growth of VNFs onto graphene nanosheets, and explicated as electrode material for supercapacitor applications. The existence of non-covalent interactions between VNFs and graphene surfaces was confirmed by Raman and Fourier...

Polymer blends yield carbon materials with superior performances for supercapacitor applications since blending can lead to controlled and fine pore architectures. In this study, a supercapacitor electrode material derived from an immiscible polymer blend comprising polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) was investigated. PAN wa...

immiscible polymer blends based on a selective polymer and a highly permeable polymer were prepared as flat membranes and tested for gas separations. Additives such as metal organic frameworks (MOF) function as compatibilizers and were demonstrated to have control over the membane microstructure where the MOF resides at the interface. SEM,TEM amd A...

The MIL-53 metal organic framework (MOF) is known to change reversibly from an open-pore framework (MIL-53-ht) to a closed-pore framework (MIL-53-lt) depending on the temperature, pressure, or guest molecules absorbed. Three frameworks of the additive, MIL-53-as synthesized (MIL-53-as), MIL-53-ht, and MIL-53-lt, were prepared, characterized, and co...

Crystals of highly soluble metal-organic polyhedra 18 (MOP 18) were synthesized and used as additives in Matrimid (R) 5218 to form mixed-matrix membranes. The MOP-18 linker was functionalized with long alkyl chains to help the crystals dissolve in Common organic solvents. Scanning electron microscopy images revealed that the MOP-18 molecules do not...

In order to achieve high energy density, electrodes used in supercapacitors should have high surface area that is accessible to the electrolyte. In this study, porous carbon nanofiber electrodes were prepared by electrospinning a solution of copolymer poly(acrylonitrile-co-vinylimidazole), (PAN-VIM) with and without incorporation of ammonium bicarb...

Electrochemical double layer capacitors (EDLCs) utilize electrodes with high surface area to achieve high-energy storage capability. In this study, flexible and freestanding carbon nanofibers derived from PIM-1, a microporous polymer with high free volume, were prepared by pyrolysis of the electrospun polymer. A BET surface area of 546 m2 g−1 was o...

In thisstudyMnO2 nanorodes (MNR)werefabricatedonreducedgrapheneoxide(rGO)sheets using afacilehydrothermalsynthesisroute.AspreparedbinderfreeMNR-rGOelectrodes exhibited promisingelectrochemicalperformance.Asimilarapproachwasemployedtoprepare V2O5 nanowire (VNW)onrGOelectrodesasanodesforsupercapacitorapplications.TheVNW- rGO anodeandMNR-rGOcathodewer...

An aspect of the invention is directed to a polymer comprising a sulfonated PerfluorocycIopentenyl compound. Another aspect of the invention is directed to a sulfonated copolymer comprising one or more sulfonated polymers. A further aspect of the invention is directed to membranes prepared from the polymers of the claimed invention.

An instrument was built for the permeation testing of flat polymer membranes under pressures up to 3.0 MPa and temperatures up to 300 °C. The high pressure, high temperature cell uses aluminum tape and a graphite gasket to minimize the leak from the high pressure side to the low pressure side, making possible the permeability measurements of slow d...

The demand for cost-efficient separations requires membranes with high gas flux and high selectivity which opens the path for further improvements. Mixed matrix membranes (MMMs) made from 33.3 wt % ZIF-8 in 6FDA-durene were tested at 35 °C and 3.5 atm. At 33.3 wt % loading of ZIF-8, H2, N2, O2, and CH4 gas permeabilities increased approximately 400...

Vanadium oxide has attracted interest for energy storage applications due to its high theoretical capacitance and stable layered structure. The low electronic conductivity, of V2O5 necessitates combining with conducting materials, typically carbon. However combining with conductive carbon materials may require binders, which compromise the active s...

A phase-separated morphology, as observed in block copolymers, for proton exchange materials (PEM) is expected to result in improved PEM fuel cell performance. Blending hydrophilic and hydrophobic polymers provides an easier route to this phase-separated morphology especially for an otherwise difficult block copolymer synthesis. Blends of hydrophil...

a b s t r a c t Exfoliated graphite nanoplatelet (xGnP) and V 2 O 5 nanotube (VNT) composite electrodes were fabri-cated and tested as electrodes for supercapacitors. Enhancement of the electrochemical performance of the composite over its component materials was demonstrated using cyclic voltammetry (CV), con-stant current charge/discharge testing...

A novel symmetrical alkylsulfonyl-substituted poly(phenylenevinylene) derivative, poly [2,5-bis-(2'-ethylhexylsulfonyl)-1,4-phenylene)vinylene] (SO2EH-PPV), was synthesized via palladium-catalyzed Stille coupling and its electronic and optical properties were investigated. The novel PPV derivative was characterized by NMR, UV-Visible absorption, ph...

Carbon nanofibers (CNFs) were fabricated by thermal treatment of electrospun nanofibers obtained from precursor blends of polybenzimidazole (PBI) and Matrimid®. The microcarbon structures of CNFs obtained from PBI, and the 50:50 and 75:25 blends were studied using XRD and Raman spectra. Nitrogen adsorption/desorption measurements revealed that surf...

Graphene is a promising electrode material for energy storage applications. The most successful method for preparing graphene from graphite involves the oxidation of graphite to graphene oxide (GO) and reduction back to graphene. Even though different chemical and thermal methods have been developed to reduce GO to graphene, the use of less toxic m...

Carbon nanofibers were prepared using electrospinning and thermal treatment of a new precursor, poly(acrylonitrile-co-vinylimidazole). Raman spectroscopy confirmed carbonization. Steam activation resulted in high surface area of 1120 m2/g. Coin cells were assembled using ethylmethylimidazolium bis(trifluoromethylsulfonyl) imide (EMITFSI) as the ele...

Polyacrylonitrile/poly(methyl methacrylate) (PMMA) fibers containing graphene are prepared by the electrospinning method, and hierarchical porous carbon nanofibers (CNFs) are obtained after subsequent heat treatment. The hierarchical porous CNFs have an improved structure and properties because of the increased surface area, unique nanotexture and...

In this study, we explore the effect of the dialkoxy and dithioalkoxy side chains on the benzo [1,2-b:4,5-b′]dithiophene (BDT) unit by comparing the O-BDT homopolymer (O-PBDT), S-BDT homopolymer (S-PBDT), and S-BDT-alt-O-BDT copolymer (SO-PBDT) by computational calculations and experimental results. The polymers were prepared by Pd-catalyzed Stille...

6FDA based polyimides offer thermal stability and remain as flexible membranes even upon incorporation of a high loading of additives. Mixed matrix membranes (MMMs) were fabricated incorporating zeolitic imidazolate framework-8 (ZIF-8) in 6FDA-durene up to 100% (w/w) loading, and a large (765%) increase in H2 permeability was observed without a los...

Non-precious metal membranes that operate at high temperatures (≥300 oC) and pressures (≥15 atm) are required by 2015 DOE targets for hydrogen separation membranes. Mixed-matrix membranes (MMMs) comprising thermally and chemically stable zeolitic imidazolate framework (ZIF) materials and thermally stable polymers that display high permselectivity c...

Lead-based nanocrystals (NCs) are promising materials for high-efficiency solar cells since they are able to generate multiexcitons with high efficiency. One complication of utilizing these NCs is the insulating ligands capping their surfaces. In this paper, we have successfully developed and characterized a phosphonate-functionalized poly-3-hexylt...

Exfoliated graphite nanoplatelet (xGnP) and V2O5 nanotube (VNT) composite electrodes were fabricated and tested as electrodes for supercapacitors. Enhancement of the electrochemical performance of the composite over its component materials was demonstrated using cyclic voltammetry (CV), constant current charge/discharge testing and electrochemical...

Novel proton conducting composite membranes were synthesized by blending Nafion® polymer with sulfonated organosilicon dendrimers (G3-S). Blending G3-S with Nafion resulted in stable, flexible membranes with loadings up to 10% by weight. The high amount of sulfonic acid groups on the dendrimer increased the ion exchange capacity and improved the wa...

Mixed-Matrix Membranes (MMM) could provide a near term solution to the permeability/selectivity trade-off with polymeric gas separation membranes and bridge the gap with inorganic membranes. While zeolite and carbon additives have shown promise, the correspondingmixed-matrix membranes are limited by low loadings and interfacial defects such that th...

Vanadium oxide nanotubes have shown great promise as electrode materials for energy storage devices. In this study, we report the synthesis of V(2)O(5) nanotube (VNT) clusters, which form densely packed radial arrangements of VNTs on high-surface-area carbon fiber fabrics (CF). This was achieved by coating the CF with V(2)O(5) by pulsed laser depos...

Vanadium pentoxide (V2O5) layered nanostructures are known to have very stable crystal structures and high faradaic activity. The low electronic conductivity of V2O5 greatly limits the application of vanadium oxide as electrode materials and requires combining with conducting materials using binders. It is well known that the organic binders can de...

A new dialkylthio benzo[1,2-b:4,5-b']dithiophene (S-BDT) was designed and synthesized and the polymer S-PBDT was prepared by a Stille coupling reaction. A high open-circuit voltage (V(oc)) of up to 0.99 V was achieved in polymer solar cells with PCBM.

The phenoxachalcogenines have been studied as donors towards 7,7,8,8-tetracyanoquinodimethane. For the 1:1 complexes studied, the equilibrium constants, K, vary over the range 4–6; the enthalpy, ΔH0, is about −2.0 kcal/mol; the free energy, ΔG0, is −1.4 to −1.0 kcal/mol, and the entropy change, ΔS0, is −7.3 to −3.5 eu. The entropy change is greates...

We report a nearly twofold increase of short circuit current: from Isc ∼ 10 mA/cm2 to Isc = 16–20 mA/cm2 in P3HT/PCBM solar cells (SC) employing freshly prepared regio-regular poly(3-hexylthiophene) (RR-P3HT) without special purification. The power conversion efficiency is enhanced to η≥ 4% as compared to our best η=3.8% in SC with commercial polym...

We describe the factors affecting the electron transfer process between the different components of a self-assembled mixed monolayer. The system is comprised of mixed monolayers containing aminoalkanethiols (AMATs) and ferrocenylalkanethiols (FATs) of variable chain lengths. We study the effects of different ratio of the two mixed monolayer compone...

Zeolitic imidazolate frameworks (ZIFs), that have the potential for gas separation, were used as additives in mixed-matrix membranes (MMMs). ZIF-8, which exhibits the sodalite topology, is composed of zinc (II) ion clusters linked by imidazolate ligands. The ZIF-8 pore aperture is 3.4Å allowing it to readily absorb small molecules such as H2 and CO...

of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.