Woven Carbon Fabric Research Articles

Phytic acid controlled in situ synthesis of amorphous cobalt phosphate/carbon composite as anode materials with a high mass loading for symmetrical supercapacitor: amorphization of the electrode to boost the energy density.

Transition metal phosphate (TMPi)-based composites as anode electrode materials in supercapacitor applications are less reported. Herein, we report a phytic acid (PA)-assisted in situ-formed amorphous cobalt phosphate/carbon (CoPi/C) composite grown on a flexible woven carbon cloth (CC) via a simple one-step carbonization approach. The tunable synthesis of amorphous and crystalline composites is shown by simply controlling the concentration of the cobalt salts. The strategy for high mass loading to 12 mg cm−2 is also shown in this report. Importantly, the resulting amorphous electrode materials exhibit electric double-layer capacitance (EDLC) behavior that works over a wide potential range from −1.4 to +0.5 V in an aqueous solution of potassium hydroxide (2 M KOH) and from −1.5 to +1.5 V in sodium sulfate (1 M Na2SO4). The amorphous electrode as an anode is capable of delivering an areal capacitance up to 2.15 F cm−2 at a current density of 4 mA cm−2 (gravimetric capacitance up to 606.1 F g−1 at 1 Ag−1) and has a retention of 94.2% at 10 000 cycles. The flexible solid-state symmetric device fabricated shows an energy density of approximately 620.0 μW h cm−2 at a power density of 4.7 mW cm−2 (31.1 W h kg−1 at 476.0 W kg−1). This study offers a novel route for the generation of metal phosphate-based anode materials with high capacitance for symmetrical supercapacitor device with high energy density.

Electromagnetic shielding effectiveness of carbon yarn-based woven fabrics

In this study, hybrid and 100% carbon woven fabrics have been investigated for their electromagnetic shielding performance in the frequencies, ranging from 700 MHz to 3 GHz. The shielding effectiveness of plain, twill, and satin woven fabrics was assessed by free space measurement technique. The experimental results showed that carbon-based woven fabrics have an optimum electromagnetic shielding efficiency at different measured frequencies. As expected, the shielding effectiveness of the structure improved with the amount of carbon yarn in the fabric structure. Analyses of the different weave types revealed that twill 2/1 fabric construction showed the best performance compared to the others due to the large number of intersection points of yarns in the fabric structure.

Structure and Properties of Polysulfone Filled with Modified Twill Weave Carbon Fabrics.

Carbon fabrics are widely used in polymer based composites. Nowadays, most of the advanced high-performance composites are based on thermosetting polymer matrices such as epoxy resin. Thermoplastics have received high attention as polymer matrices due to their low curing duration, high chemical resistance, high recyclability, and mass production capability in comparison with thermosetting polymers. In this paper, we suggest thermoplastic based composite materials reinforced with carbon fibers. Composites based on polysulfone reinforced with carbon fabrics using polymer solvent impregnation were studied. It is well known that despite the excellent mechanical properties, carbon fibers possess poor wettability and adhesion to polymers because of the fiber surface chemical inertness and smoothness. Therefore, to improve the fiber–matrix interfacial interaction, the surface modification of the carbon fibers by thermal oxidation was used. It was shown that the surface modification resulted in a noticeable change in the functional composition of the carbon fibers’ surface and increased the mechanical properties of the polysulfone based composites. Significant increase in composites mechanical properties and thermal stability as a result of carbon fiber surface modification was observed.

Experimental characterization of the inter-ply shear behavior of dry and prepreg woven fabrics: Significance of mixed lubrication mode during thermoset composites processing

A custom-built test device was developed to measure the inter-ply shear resistance of dry carbon woven fabrics as well as prepregs at different temperatures, consolidation pressures, and forming rates typical to those used in autoclave processing. A quantitative understanding of the nature of the shear forces encountered during fabric consolidation was established, suggesting the strong dependence of these forces on the process conditions along with the dominance of a mixed lubrication regime. Among the most influential state variables, the resin viscosity and distribution of the resin on the prepreg surface, as well as the surface roughness of the reinforcing fibers could be identified.

Highly porous self-assembly of nitrogen-doped graphene quantum dots over reduced graphene sheets for photo-electrocatalytic electrode

Nitrogen-doped graphene quantum dots (NGQDs) are a diverse organic catalyst, competitive with other metallic catalysts due to their low cost, high stability, biocompatibility, and eco-friendliness. Highly functional multi-edge surfaces of NGQDs play a key role in imparting superb photocatalytic and electrocatalytic activity. However, when coating NGQDs by conventional techniques, such surfaces are not exposed for catalysis, due to the unwanted overlap of NGQDs sheets. To avoid this issue, here we propose a facile technique to orient NGQDs in a three-dimensional (3D) self-assembled foam-like structure, over reduced graphene oxide coated woven carbon fabric. This 3D assembled structure provides highly exposed active surfaces, which are readily available for catalytic reactions: however, in the conventional uniformly coated NGQDs layer, catalytic activity was limited by complex diffusion. The superb catalytic activity of the assembled NGQDs was utilized for the degradation of organic pollutant (methylene blue dye) from water. Additionally, the proposed electrode revealed much higher electrocatalytic activity than the rare Pt catalyst, owing to the easy diffusion of electrolyte and fast quenching of charges through the porous structure. The assembled NGQDs showed 50% higher photocatalytic degradation compared to uniformly coated NGQDs, which was further accelerated (50%) by application of the biased potential of 2 V; i.e. photo-electrocatalysis. The novel photo-electrocatalytic electrode offers high conductivity, stability, and flexibility, which make this complete carbon electrode highly attractive for other catalytic applications such as fuel cells, supercapacitors, and water splitting.

Pulse electrodeposited manganese oxide on carbon fibers as electrodes for high capacity supercapacitors

Arrays of manganese dioxide (MnO2), a pseudocapacitive material, have been deposited on the carbon fibers (CF) of a carbon woven fabric by electrodeposition from a solution containing manganese sulfate and sulfuric acid using galvanostatic square waves. The thickness of the MnO2 was varied by increasing/decreasing the time of deposition, and the electrochemical performance of the MnO2 has been analyzed. The CF serves as a substrate material with high surface area, good electrical conductivity and excellent mechanical strength. The electrochemical properties of the resultant electrode were examined by cyclic voltammogram (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscopy in a three-electrode system. From the specific capacitance calculations obtained from CV and charge–discharge, a high specific capacitance of 769 F g−1 @ 5 mV s−1 (low weight electrode) has been achieved. The maximum area capacitance, estimated from the charge–discharge curves, was 790 mF cm−2 @ 5 mV s−1. The high-performance is attributed to the double layer capacitance of the CFs combined with the pseudocapacitive nature of MnO2, the large surface area, and high degree of ordering of the ultrathin MnO2.

Preparation of Ti-based laminated composites through spark plasma sintering with different carbon sources as the bonding layer

In the present study, woven carbon fabrics, graphene nano sheets (GNPs) and graphites were used as the bonding source between Ti sheets to produce Ti-TiC laminated composites through spark plasma sintering. In the case of carbon fibers, the woven fabrics were cut in a circular shape and inserted between the Ti sheets; on the other hand, in the case of graphite and GNPs, ethanol with carbon sources as the mixture was sprayed on the surface of the starting Ti sheets until reaching the specified increase in the weight of the coated Ti. After that, seven layers of Ti sheets (including six coated layers and one un-coated one) were inserted to the graphite die and the sintering process was performed with the initial and final applied pressure of 10 and 50 MPa, respectively, at the sintering temperature of 1250 °C. The XRD patterns taken from the cross-section of the prepared composites revealed the formation of the TiC crystalline phase as the product of the reaction between Ti and the carbon sources. The FESEM images also showed the proper bonding between the layers due to the formation of TiC and carbon diffusion into the Ti sheets. The fracture surfaces of the prepared sample demonstrated the almost ductile fracture for the Ti-laminated sample, as well as the Ti-GNPs laminated composite, while the brittle fracture was obtained for the composites with graphite and the carbon fabric as the bonding layers. The highest hardness of 912 ± 17 Hv was calculated for the cross-section of the Ti-CF laminated composite; also, the highest bending strength of 1215 ± 18 MPa was obtained for the Ti-GNPs laminated composite.

Lightweight metallic matrix composites: Development of new composites material reinforced with carbon structures.

Carbon nano/micro-structures used as fillers in metallic lightweight alloy matrix composites are receiving considerable attention in scientific research and industrial applications. Aluminum and magnesium are the most studied light metals used as matrices in metal composites materials, principally for their low density (respectively 2.7 g/cm3 and 1.7 g/cm3) and low melting temperature (around 660 °C for both metals). A good interaction between matrix and fillers is the first step to obtain an increase in bulk properties; furthermore, the manufacturing procedure of the composite is fundamental in terms of quality of fillers dispersion. In this work the influence of surface modifications for three classes of carbon fillers for aluminum and magnesium alloy (AZ63) as matrices is studied. In particular, the selected fillers are short carbon micro fibers (SCMFs), carbon woven fabrics (CWF), and unidirectional yarn carbon fibers (UYFs). The surface modification was carried out by a direct coating of pure nickel on fibers. The electroless pure nickel plating was chosen as the coating technique and the use of hydrazine as reducing agent has prevented the co-deposition of other elements (such as P or B). Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses were performed to study the effect of surface modifications. The mechanical properties of manufactured composites were evaluated by 4-point flexural tests according to ASTM C1161 (room temperature). Results confirm improved interactions between matrix and fillers, and the specific interaction was studied for any chosen reinforcement.

Improvement of mechanical properties of hybrid composites through interply rearrangement of glass and carbon woven fabrics for marine application

Glass fiber reinforced polymer composites (GFRPC) possess low strength in comparison to carbon fiber reinforced polymer composites (CFRPC). The degradation of the mechanical properties of seawater aged GFRPC is more than that of CFRPC. However, CFRPC is not commercially viable for all type of applications due to its high cost. Therefore, there is a need to hybridize carbon fiber with glass fiber to overcome the weakness of glass fiber reinforced polymer composites for marine application. In this investigation, there are five types of composites were considered, i.e., plain glass ([G]s), plain carbon ([C]s), [G3C2]S, [G2C2G]S and [GCG2C]S type of hybrid composites. The composites were seawater aged for 90 days. The results revealed that the tensile strength of seawater aged [GCG2C]S type hybrid composite was improved by 14% as compared to plain GFRPC. The flexural strength and modulus of seawater aged [GCG2C]S type hybrid composite were enhanced by 43% and 64% respectively in comparison to plain GFRPC. However, the impact strength of seawater aged [GCG2C]S type hybrid composites was reduced by 44.5% as compared to plain GFRPC. Furthermore, the structure-properties co-relationship was established from field emission scanning electron microscopy images.

Property enhancement of CFRP composites with different graphene oxide employment methods at a cryogenic temperature

In this study, graphene oxide (GO) was used to improve the mechanical properties of carbon fibre reinforced polymer (CFRP) composites at room temperature (RT) and cryogenic temperature (CT). It was found that GO could effectively improve the mechanical properties of CFRP composites at both temperature conditions as compared to pristine composites, particularly at CT due to its unique thermal response. Two approaches of employing GO into CFRP composites, either dispersing GO into epoxy matrix or coating it onto the surface of carbon woven fabric (CWF) were also investigated and compared. The results showed that GO devoted to a more significant improvement in the mechanical properties of composites when it was employed on the surface of CWF. It was also discovered that the flexural strength and modulus of CFRP composites were reduced at CT by 8.74% and 10.63% respectively, but the addition of GO would help restrict the degradation of matrix and limit the reduction to 1.15% and 2.09% respectively, and thus retain its enhanced mechanical properties.

Electrical resistance heating for deicing and snow melting applications: Experimental study

In this study, a novel electrical resistance heating method for deicing and snow melting applications was investigated. Three different forms of carbon fiber were embedded into concrete specimens and their heating performances were tested. To simulate the condition of concrete exposed to low temperatures, an environmental chamber was utilized. The effect of various parameters such as heat power density, ambient temperature, heating panel installment depth, concrete moisture and form of carbon fibers on temperature changes was investigated. Experimental results showed that carbon fiber electrical heating can offer viable solution for icing and snow accumulation problems. Compared to other heated pavement systems, it has relatively lower installment and material cost. The power densities of a heating system should be designed depending on a specific application. Otherwise, successful deicing operation may not be guaranteed. Using carbon fiber in cable form provides many advantages compared to using woven and unidirectional carbon fabrics. Placing heat panels close to concrete surface affected heating performance positively but long term integrity of heat panels may be affected by placing them very close to the surface. Even though some decrement was observed, moisture in concrete did not significantly degrade the heating performance.

Development and Evaluation of a CFL Diagram Method for Notched Fatigue of Plain Weave Carbon Fabric Composite Laminates

Development and Evaluation of a CFL Diagram Method for Notched Fatigue of Plain Weave Carbon Fabric Composite Laminates

Analysis of the multilayer woven fabric behaviour during the forming process: focus on the loss of cohesion within the woven fibre network

The first step in the composite manufacturing process consists of forming a flat textile reinforcing structure into a 3D shape. The quality of the final composite part is affected by the presence of defects induced during the forming process. Loss of cohesion in the woven fibre network (intra-ply yarn sliding) is a frequent defect in the forming process. It is expected when the cohesion between the yarns is weak or when the blank holder pressure is high. However, the mechanism of formation of this defect is not fully understood. In the present study, forming experiments with friction-based holder have been conducted for a monolayer twill woven carbon fabric in two orientations and for two plies of this fabric with different relative orientations. The occurrence of the intra-ply yarns sliding has been observed as a function of the blank holder pressure. A correlation between the occurrence of this defect and the fabric orientation has been noticed. Furthermore, the effect of the fabric orientation, number of plies, relative plies orientation and blank holder pressure on the recorded forming force and on the fabric in-plane shear is also reported and analysed.

Prediction of Defect Formation during Resin Impregnation Process through a Multi-Layered Fiber Preform in Resin Transfer Molding by a Proposed Analytical Model

It is very important to predict any defects occurring by undesired fiber deformations to improve production yields of resin transfer molding, which has been widely used for mass production of carbon fiber reinforced composite parts. In this study, a simple and efficient analytic scheme was proposed to predict deformations of a multi-layered fiber preform by comparing the forces applied to the preform in a mold of resin transfer molding. Friction coefficient of dry and wet states, permeability, and compressive behavior of unidirectional (UD) and plain woven (PW) carbon fabrics were measured, which were used to predict deformations of the multi-layered fiber preforms with changing their constitution ratios. The model predicted the occurrence, type, and position of fiber deformation, which agreed with the experimental results of the multi-layered preforms.

Electrical resistance and microstructure of typical gas diffusion layers for proton exchange membrane fuel cell under compression

Electrical resistance accounts for a significant part of the performance loss in proton exchange membrane fuel cells. To the best of the authors’ knowledge, this work represents the first direct experimental investigation and comparison of the bulk resistance and microstructure of commercially available gas diffusion layers, carbon paper, carbon cloth and carbon felt, under cyclic and steady loads, which are typical compression conditions in the fuel cell. It was found that with the improvement of contact conductivity between gas diffusion layer and bipolar plate, the bulk resistance of gas diffusion layer accounts for as much as 20% of the resistance in the fuel cell, especially when the assembly pressure is high enough. Experimental results indicate that three kinds of gas diffusion layers show various electrical behaviors under compression due to their different fiber structures. For carbon paper, the resistance displays a gradual decline as the load cycles increases. A reduction in the resistance and obvious fiber cracks are observed when the compression pressure exceeds the “break stress” of 2.0 MPa. For woven carbon cloth, more uniform decline of the resistance is caused by the increasing fiber cracks, which are pulled and bent in the middle of a weave. Although felt gas diffusion layer features the lowest electrical conductivity, its tortuous and thick fibers lead to higher stability in electric resistance and microstructure than bonded carbon paper and woven carbon cloth. This study is helpful for enhancing our understanding of the relationship between electrical resistance and compression loads in the fuel cell with various gas diffusion layers.

Analysis on temperature-dependent deployment behavior of bi-stable composite rods

Bi-stable composite rods attract many researchers to investigate the mechanical and deployment behaviors for possible application to space deployable structures. Operation requires the bi-stable composites to be in a compact form prior to deployment. The deployment behavior is influenced by the storage conditions and the environmental temperature, of which, the latter is focused on in the present study. This study utilizes plain woven carbon fabrics composites to make bi-stable composites. Temperature-dependent mechanical properties of bi-stable composites are measured, and temperature-dependent deployment forces of bi-stable rods are evaluated using analytical formulations and finite element simulations with the measured properties.

Flexural fatigue behavior of LSI based plain weave carbon fabrics reinforced ceramic composites

An experimental investigation was performed to study the fatigue behavior of plain-weave fiber fabrics reinforced C/C-SiC composites (2D C/C-SiC composites) prepared by liquid silicon infiltration (LSI) under dynamic flexural stresses at room temperature. The results indicate that the fatigue limit (105 cycles) of 2D C/C-SiC composites subjected to flexural fatigue stresses is 95 MPa, corresponding to approximately 78% of flexural strength of virgin specimens. Moreover, as the fatigue loading/unloading proceeds, both strength enhancement and strength degradation are successively observed in the post-fatigue specimens under quasi-static flexural tests. Maximum residual flexural strength (RFS) of post-fatigue specimens increases to 135.7 MPa when the 2D C/C-SiC specimens are exposed to maximum fatigue stress of 95 MPa for 5000 cycles. The microstructures and fractured surfaces indicate that evolution of RFS is determined by the interaction of matrix cracking and interfacial degradation. The interfacial debonding and relief of residual thermal stresses induced by matrix cracking are mainly responsible for the enhanced strength in the post-fatigue specimens.

Electroless Encapsulation of C-Cloth with Sn and Sn-Cu Alloy for Li-Ion Battery Anode

Over the last few decades a vast number of researchers have investigated various methods for the synthesis of tin alloy anode materials capable of repeated cycling, reduced tin pulverization, and capacity retention when used in lithium ion batteries (LIBs).1-3 In this study, we report the use of woven carbon cloth as high surface area template for the deposition of Cu and subsequent encapsulation with Sn via facile electroless coating method without the use of external power supply. The resulting material Sn-Cu@C-cloth was annealed at 200 OC and 400 OC and used as electrodes in LIB half-cells with Li metal as anode. Charge/discharge study at current density of 227 mAh/g indicated that Sn-Cu@C-cloth annealed at 200OC and 400 OC exhibited first cycle capacities of 745 mAh/g, and 1075 mAh/g, respectively, while the C-cloth substrate exhibited only 340 mAh/g. Preliminary results after fifty cycles indicated that the annealed Sn-Cu@C-cloth exhibited capacity retention of ~413 mAh/g. These results indicate that facile electroless encapsulation of carbon cloth as a cost effective approach can potentially be used to fabricate Sn and CuSn alloys anode materials.

In-situ growth of high-performance all-solid-state electrode for flexible supercapacitors based on carbon woven fabric/ polyaniline/ graphene composite

For the development of wearable electronic devices, it is crucial to develop energy storage components combining high-capacity and flexibility. Herein, an all-solid-state supercapacitor is prepared through an in-situ “growth and wrapping” method. The electrode contains polyaniline deposited on a carbon woven fabric and wrapped with a graphene-based envelop. The hybrid electrode exhibits excellent mechanical and electrochemical performance. The optimized few layer graphene wrapping layer provides for a conductive network, which effectively enhances the cycling stability as 88.9% of the starting capacitance is maintained after 5000 charge/discharge cycles. Furthermore, the assembled device delivers a high areal capacity (of 790 F cm−2) at the current density of 1 A cm−2, a high areal energy (28.21 uWh cm−2) at the power densities of 0.12 mW cm−2 and shows no significant decrease in the performance with a bending angle of 180°. This unique flexible supercapacitor thus exhibits great potential for wearable electronics.

Perspective on Carbon Fiber Woven Fabric Electrodes for Structural Batteries

The purpose of this work is to explore effective means of fabricating nanostructure-deposited continuous woven carbon fabric and to investigate the feasibility of using this material in structural battery applications. In order to prove this concept, two types of nanostructured carbon fabric electrodes – one with vertically-aligned carbon nanotubes (VACNTs) formed directly on carbon fabric utilizing iron (Fe) nanoparticles and Al buffer layers, the other with the same VACNTs on a chemical vapor-deposited graphene surface utilizing Ni seed layers on the carbon fabric – were fabricated to investigate material electrical performances as battery electrodes. The reversible specific capacity of 250 mAh/g on average at C/20 with good cyclic retention in these three all-carbon electrodes, including pristine carbon fabric, suggests a promising structural battery electrode for low-current battery applications. Even though the capacity of VACNT-grafted carbon fabrics was limited due to poor wetting of the VACNT forest with electrolyte caused by the lack of functionalization of the VACNT, their excellent cyclic performances and galvanostatic curves support the idea that the carbon nanotube and carbon fabric combination can be utilized in battery applications. However, pristine-carbon fabric is still a good candidate for battery applications because of its simplicity of mass production.