Carbon Fiber Surface Research Articles

Construction of multilayer carbon magnetic heterostructures on the surface of carbon fibers to improve the absorption performance

AbstractThis study utilizes the strong complexation effect of polydopamine on metal ions and constructs multilayer carbon magnetic heterostructures on the surface of carbon fibers through the in situ reduction method, thereby obtaining a new type of multilayer carbon‐based composite absorbing material. The absorption properties at different layers were analyzed and compared through various characterization methods. Finally, the double‐layer structure demonstrated outstanding electromagnetic wave absorption characteristics, exhibiting a wide effective absorption bandwidth of 7.24 GHz and robust absorption of −44.48 dB, all within a mere thickness of 3.5 mm. Therefore, excellent market prospects for this material are anticipated.Highlights A multilayer carbon magnetic heterostructure absorbing material was constructed on micrometer‐scale carbon fibers. The test results show that a wide effective absorbing bandwidth of 7.24 GHz and a minimum reflection loss of −44.48 dB are obtained when the composite thickness is 3.5 mm. The prepared multilayer absorbing composites can adapt to a variety of application scenarios and have excellent application prospects in the industry. The self‐polymerization of dopamine and complexation of metal ions were used to construct multilayer absorbing materials, and the dielectric loss and magnetic loss capacity of the carbon fibers improved.

Effect of polyphenylene sulfide sulfone sizing agent on interfacial, thermal, and mechanical properties of carbon fiber

AbstractPolyphenylene sulfide sulfone (PPSS) was synthesized by one‐step method and utilized as a sizing agent for carbon fibers. The effects of various monomer ratios, reaction time, and reaction temperature were investigated on the molecular weight of PPSS. The thermal analysis revealed that the product PPSS exhibited a glass transition temperature exceeding 215.5°C, indicating exceptional thermal stability. After PPSS sizing treatment, the grooves on the surface of carbon fibers were filled, resulting in a substantial enhancement of the microinterface properties. The surface energy was increased by 8.2%, while the maximum weight loss temperature was 27.8% higher than that of the commercial carbon fiber. The tensile strength of the carbon fiber after heat treatment reached 2196 MPa, representing a 45.9% increase over that of the commercial carbon fiber.

Sustainable and Low-Cost Electrodes for Photocatalytic Fuel Cells.

Water pollutants harm ecosystems and degrade water quality. At the same time, many pollutants carry potentially valuable chemical energy, measured by chemical oxygen demand (COD). This study highlights the potential for energy harvesting during remediation using photocatalytic fuel cells (PCFCs), stressing the importance of economically viable and sustainable materials. To achieve this, this research explores alternatives to platinum cathodes in photocathodes and aims to develop durable, cost-effective photoanode materials. Here, zinc oxide nanorods of high density are fabricated on carbon fiber surfaces using a low-temperature aqueous chemical growth method that is simple, cost-efficient, and readily scalable. Alternatives to the Pt cathodes frequently used in PCFC research are explored in comparison with screen-printed PEDOT:PSS cathodes. The fabricated ZnO/carbon anode (1.5 × 2 cm2) is used to remove the model pollutant used here and salicylic acid from water (30 mL, 70 μM) is placed under simulated sunlight (0.225 Sun). It was observed that salicylic acid was degraded by 23 ±0.46% at open voltage (OV) and 43.2 ± 0.86% at 1 V with Pt as the counter electrode, degradation was 18.5 ± 0.37% at open voltage (OV) and 44.1 ± 0.88% at 1 V, while PEDOT:PSS was used as the counter electrode over 120 min. This shows that the PEDOT:PSS exhibits an excellent performance with the full potential to provide low-environmental-impact electrodes for PCFCs.

Carbon Fiber Reinforced Recycled Polypropylene/Polyolefin Elastomer Composites with High Mechanical Properties.

The treatment of waste plastics has gradually become a hot topic in the current scientific community. In response to the needs for high-impact performance R-PP-based composites, carbon fiber (CF)-reinforced polyolefin elastomer (POE)/recycled polypropylene (R-PP) composite (CF/POE/R-PP) was prepared by the mechanical blending method, and its mechanical and thermal properties were systematically studied. It was found that the CF could effectively improve the bending and notch impact strength as well as enhance the thermal stability of POE/R-PP. Furthermore, a stable and dispersed composite interface formed by the combination of maleic anhydride-grafted polypropylene (PP-g-MAH) with the surface of CF and the fusion alkyl chains in R-PP and POE further enhanced the CF's reinforcing effect. As a result, the addition of 9 wt.% CF successfully improved the heat resistance of the composite material, and the residual carbon content increased by 97.84% after sintering. The composite toughening of POE and CF effectively improved the impact strength of the composite material, with a maximum increase of over 1000%. This study ultimately resulted in a high-impact-resistant composite material.

Improving the thermal conductivity of an epoxy composite with chemically boron nitride-grafted carbon fiber

The rapid progress of electronic devices like electric vehicles, smartphones, and IoT systems has fueled the demand for compact, high-performance batteries. However, a critical challenge arises from heat accumulation within these devices, leading to malfunctions and reduced efficiency. To address this, efficient heat dissipation is crucial, with thermal interface materials (TIMs) widely used for heat transfer. While polymers are favored for TIMs due to their ease of processing and electrical insulation, their low thermal conductivity poses limitations. In this study, a solution is proposed by chemically grafting boron nitride (BN), a ceramic-based filler, onto carbon fiber (CF) surfaces. This BN-g-CF hybrid filler, formed through a reaction between acyl chlorides and amine groups, exhibits superior compatibility with polymer matrix. Characterization confirms successful treatment, and thermal conductivity measurements show a remarkable enhancement, positioning the BN-g-CF/epoxy resin composite as a promising solution for efficient thermal management in various electronic industries.

Preparation of biomimetic reinforced modified carbon fiber composites and study of their friction properties

Because aluminum-based parts cannot be used for long-term applications in large load-wear environments, nickel–tungsten (molybdenum disulfide)/carbon fiber/aluminum composites were successfully prepared in this study for that purpose. By adjusting the plating solution ratio, nickel–tungsten was used as a carrier to introduce molybdenum disulfide nanoparticles, forming a nickel–tungsten/molybdenum disulfide composite coating on the surface of carbon fibers. To enhance the interfacial bonding strength between the carbon fiber and aluminum matrix, a laser was employed to induce the formation of a honeycomb-like structure on the surface of the aluminum base. This increased the contact area between the carbon fiber, aluminum matrix, and epoxy resin adhesives, forming a nickel–tungsten (molybdenum disulfide)/carbon fiber/aluminum composite material. The performance of this composite material was tested and analyzed. The results demonstrated that compared with the carbon fiber/aluminum composite material, the shear strength of the nickel–tungsten (molybdenum disulfide)/carbon fiber/aluminum composite material was increased by 129.7 %, and the friction coefficient and wear rate were reduced by 54.8 % and 83 %, respectively. Next, investigation of the mechanism underlying the honeycomb structure's contribution to the adhesive strength of the composites and their resistance to shear load revealed that the wear-resistant mechanism of molybdenum disulfide nanoparticles reinforced the nickel–tungsten composite coatings. The preparation and study of nickel–tungsten (molybdenum disulfide)/carbon fiber/aluminum composites provide a reference for expanding the applications of aluminum-based composite materials to meet the service requirements of complex environments.

Collaboration of Fenton reaction with a tannin acid-based hyperbranched waterborne polyurethane sizing agent for synergistic enhancement of the CF/PA6 composite interfacial properties

The adhesive strength between the sizing agent and carbon fiber (CF) plays a pivotal role in determining the interfacial properties of composites. Unfortunately, this critical aspect has been consistently overlooked. In this study, a hyperbranched waterborne polyurethane (HWPU) sizing agent was prepared by biogenetic derived raw materials including gallic acid as well as tannic acid. Meanwhile, iron ion was introduced onto the surface of CF by Fenton reaction, forming a heterogeneous structure to elevate the mechanical interlocking between the CF and resin. Chelation of TA with iron ion on the fiber surface effectively enhanced the adhesion between sizing agent and CF. The mechanical properties of the newly designed composites were systematically investigated. The results showcase a significant enhancement in both flexural strength and interlaminar shear strength (ILSS) compared to untreated CF, marking improvements of 54.3% and 60.0%, respectively. Furthermore, the interfacial shear strength (IFSS) test exhibited a 71.2% augment. In conclusion, this approach presented a highly promising concept aimed at improving the interfacial performance of CF composite materials.

Mitigating Crack Propagation in Hybrid Composites: An Experimental and Computational Study

The exceptional properties of carbon nanotubes (CNTs) make them ideal nanofillers for various composite materials. In carbon fiber-reinforced polymer (CFRP) composites. CNTs can be grown on the carbon fiber surface to act as a third interface between the fiber and the matrix. However, it was established that the uncontrolled random growth of CNTs could exacerbate delamination in composite structures. Thick nanofiller films could hinder the epoxy from seeping into the carbon fiber, resulting in insufficient interlaminar strength. Hence, the density and distribution of nanofillers play a crucial role in determining the hybrid composite fracture mechanisms. In this investigation, CNTs were grown using the low-temperature technique into specific patterns over carbon fibers to discern their derived composites’ fracture properties. The composite fracture energy release was probed using a double cantilever beam (DCB) test setup and digital image correlation (DIC) to monitor interlaminar crack propagation. A standard finite element simulation model based on the cohesive zone method (CZM) was also utilized to delineate fracture behaviors of the various composite configurations. Results conclude that a coarser pattern of CNT growth enhances resistance to crack propagation, thus improving the interlaminar fracture toughness of a composite structure.

Green synthesis of positive electrodes for high performance structural batteries - A study on graphene additives

Carbon fibres (CF) have the potential to serve as versatile and multifunctional conductive electrodes within the concept of “structural batteries”. These batteries possess the unique ability to both store electrical energy and bear mechanical loads without requiring extra current collectors. However, numerous challenges remain on the path to commercializing structural batteries. One significant challenge lies in the fabrication process of CF-based cathode composites, including the poor adhesion of active materials to the CF surface and the use of hazardous organic solvents, such as N-methyl pyrrolidone (NMP) through traditional blade coating. In this study, we present a sustainable fabrication approach, using electrophoretic deposition (EPD) to construct positive electrode composites with lithium iron phosphate (LiFePO4) and graphene nanosheets. Especially, ethanol was used as a green solvent replacing NMP to minimize the environmental impact. Meanwhile, the influence of different types of graphene additives (three kinds of graphene nanoplatelets (GNP), four kinds of reduced graphene oxide (rGO) and one home-made graphene) to the relative battery performance were evaluated under a systematic comparative analysis. Among the tested graphene additives, LFP/rGO2 based positive electrode exhibits a desirable specific capacity of 126.2 mAhg−1, maintaining over 93% retention even under the demanding conditions of 2C over 500 cycles.

Nano-Fe3O4/polymerize aniline/carbon cathode based microbial fuel cell for efficient power generation and uranium separation

Microbial fuel cells (MFCs) have gained increasing attention in the field of uranium-containing wastewater (UCW) treatment as a self-powered bioelectrochemical system (BES) due to its advantages of recovering uranium resources and generating electricity. However, the lack of catalytic active sites on the carbon fiber cathode significantly hinders the reaction performance of surface electrons with uranium ions in solution, thereby limiting the application of MFC. In this study, we propose a carbon brush (CB) cathode modification process that utilizes cyclic voltammetry synthesis technique (CVS) to polymerize aniline (PA) on the surface of carbon fibers and uniformly load nano-Fe3O4 particles (nFe3O4). The loading of PA/nFe3O4 not only significantly improve the catalytic active sites but also enhance the synergistic effect of adsorption and conductivity of CB cathode. Consequently, the nFe3O4/PA/CB-MFC showed excellent ability to continuous power generation and uranium separation. Over eight cycles of uranium separation, the nFe3O4/PA/CB-MFC exhibited an average maximum power density of 15.17 mW/m2 and a uranium separation efficiency of 95.52 %, showcasing substantial enhancements by 2.10-fold and 1.44-fold compared to the CB-MFC, respectively. Our study presents an efficient approach to enhance the efficiency of uranium separation and boost power density of MFC by increase catalytic active sites on carbon-based cathode.

Enhancement of interfacial performance of carbon fiber reinforced polypropylene composites by dual action of polyetherimide nanoparticles and coatings

In order to enhance the interfacial bonding between carbon fibers (CFs) and polypropylene (PP) resin, a multiscale modification system of composite interfacial physical embedding-chemical bonding was established by the dual action of polyetherimide (PEI) nanoparticles and coatings prepared on the surface of CFs. Hemispherical PEI nanoparticles were prepared by evaporation-induced treatment to improve the mechanical interlocking ability of the composite interface. Based on PEI nanoparticles, coatings with different concentrations were introduced on the CF surface to exert chemical bonds and enhance compatibility with the PP resin. The surface properties of CFs, including chemical composition, morphology, wettability, and interfacial adhesion were systematically investigated. Compared with unmodified CFs, modified CFs showed increased surface roughness, enhanced surface activity, and improved surface wettability. Due to the dual action of PEI nanoparticles and coatings, the tensile strength and interlaminar shear strength (ILSS) of the composite were both enhanced. Specifically, the ILSS of PCF-0.10/PP composite increased by 119.35%, indicating that the dual modification significantly improved the mechanical reinforcement and interfacial adhesion of the composite. On this basis, the interfacial strengthening mechanism in the composite was proposed, and an effective and feasible method was proposed to improve the interfacial performance of composites. The method has the limitation of a long preparation time, but it is simple, easy, and cost-effective, which provides a promising prospect for the application of composites.

Improving the interfacial adhesion between recycled carbon fibres and polyphenylene sulphide by bio-inspired dopamine for advanced composites manufacturing

Polyphenylene sulphide composites with recycled carbon fibres are of high interest due to their promising mechanical properties. Poor interface adhesion between recycled carbon fibre and thermoplastic matrix, however, remains a major problem in composite manufacturing. Herein, a novel one-step method using bio-inspired copolymerisation of dopamine to graft silica nanoparticles onto the carbon fibre surface is reported. Comprehensive investigations were conducted to fabricate the treated carbon fibre and characterise the modified samples by analysing the surface morphology and functional groups. The experimental results reveal that the network of bio-inspired adhesive polydopamine and nanoparticles adhering to the fibres can improve inter-laminar shear strength by 28.4% in the resulting composites. In addition, dynamical mechanical analysis results prove that the interfacial bonding at the fibre/matrix interface provides good resistance to thermal cycling. This novel approach introduces the functional groups on the recycled carbon fibre surface, leading to an improvement of surface energy and wettability between the carbon fibres and polyphenylene sulphide matrix and constitutes a robust and green approach to the manufacturing of advanced composites.

Flexural Properties and Failure Mechanisms of Short-Carbon-Fiber-Reinforced Polylactic Acid Composite Modified with MXene and GO.

Recently, short-fiber-reinforced thermoplastic composites (SFRTPCs) have been playing a more and more crucial role in the application of automotive interior materials due to their advantages of low density and environmental resistance properties. However, their relevant mechanical properties need to be optimized. Previous investigations revealed that the surface modification of fibers is useful to improve their mechanical properties. In this work, carbon fiber (CF)-reinforced polylactic acid (PLA) composites modified with MXene and graphene oxide (GO) were prepared by twin-screw extrusion and injection molding methods. Short CF was firstly modified with polyetherimide (PEI), then different weight ratios of MXene-GO (1:1) were subsequently modified on PEI-CF. Finally, the flexural properties and failure mechanisms were analyzed. The results showed that MXene-GO was successfully coated on CF surface, and the flexural strength and modulus of CF-PEI-MXene-GO-reinforced PLA (CF-PEI-MG/PLA) composite were improved compared to that of CF/PLA composite. In addition, the fracture sections of the composites were flat and white, and the fibers bonded well with PLA for CF-PEI-0.1MG/PLA composite compared to CF/PLA composite. The present study could provide a reference for further improving the mechanical performance of PLA-related composites.

Development of a "Rigid-Flexible" Structure at the Interface Through Aramid Nanofibers@MXene to Enhance Mechanical Properties of Carbon Fiber/Polyamide Composites.

With the increasing development of nanomaterials, the construction of multiscale nanostructured interphase has emerged as a viable technique to reinforce carbon fiber-reinforced polymer composites. Here, "flexible" aramid nanofibers (ANFs) were first introduced on the surface of carbon fibers (CF) by electrophoretic deposition (EPD), and then "rigid" MXene sheets were grafted by ultrasonic impregnation. This feasible two-step treatment introduces a hierarchical "rigid-flexible" structure at the CF/polyamide (PA) interface. Results showed that this "rigid-flexible" multilayer structure improved the roughness, chemical bonding, mechanical interlocking, and wettability of CF/PA composites. At the same time, the modulus variation between the fiber and the matrix is significantly smoothed due to the increased thickness of the interfacial layer, increasing the payload transfer from the PA matrix to the fiber and decreasing the stress concentration. Compared to the desized CF, the interlaminar shear strength (ILSS) and tensile strength of the modified CF-ANF@MX0.2/PA composite increased by 50.02 and 36.11%, respectively. This innovative interfacial design and feasible treatment method facilitate the construction of firmly interacting interfacial layers in CF/PA composites, offering broad prospects for the production of high-performance CF/PA composites.

Preparation of unsaturated self-emulsifying polyester sizing agents for improving interfacial and mechanical properties of carbon fiber/vinyl ester resin composites

In order to promote the interfacial adhesion between carbon fiber and vinyl ester matrix, a series of unsaturated self-emulsifying anionic polyester sizing agents were designed. The results indicated that the sizing agents exhibited a uniform particle size distribution at the nanometer level and demonstrated favorable thermal stability below 200 °C. As the content of double bonds of sizing agents increases, the glass transition temperature also increases, and the moisture absorption of sized carbon fiber decreases. The carbon fiber surface becomes smoother after sizing. Moreover, the interlaminar shear strength and interfacial shear strength increased by 18.8 % and 43.4 %, respectively, compared to the commercial carbon fiber. This is mainly due to the unsaturated bonds in the sizing agent react with the free radicals on the surface of the carbon fiber, which enhance the interface bonding strength between the sizing agent and the surface of the carbon fiber and the vinyl ester matrix.

Construction of “hard‐soft‐hard” structures with ammonium cerium nitrate/sodium alginate/carbon nanotubes on carbon fiber surfaces for superior mechanical

AbstractThe interface between carbon fiber (CF) and the resin matrix is of paramount importance in determining the overall performance of composite materials. This study employed ammonium ceric nitrate (ACN), sodium alginate (SA), and aminated carbon nanotubes (CNTs) to fabricate “hard‐soft‐hard” nanostructure on the surface of CFs with the aim of enhancing the interfacial properties of the composites. The results indicated that interlaminar shear strength (ILSS), interfacial shear strength (IFSS), flexural strength, and modulus of the composites demonstrated a respective increase of 31.0%, 51.8%, 44.3%, and 85.3% following the modification process. The observed positive outcome can be ascribed to the creation of “hard‐soft‐hard” nanostructures achieved by the combination of ACN, SA, and CNTs through both hydrogen and covalent bonding. The nanostructures serve to augment the surface chemical activity of the fibers and amplify the specific surface area, thereby facilitating enhanced mechanical interlocking between the fibers and the resin. Furthermore, the composites of CF prepared through this method demonstrate outstanding mechanical characteristics, rendering them appropriate for the construction of longer‐lasting and more resilient wind turbine blades.Highlights ACN, SA, and CNT create a “hard‐soft‐hard” multi‐phase structure. ACN/SA/CNT synergistically enhances composite interfacial bonding. Inorganic–organic–inorganic materials on CF form novel interfacial phases. Resultant structure improves composite interface properties.

Precision finishing of nickel-phosphorus plated carbon fibre reinforced polymer

Carbon fibre reinforced polymer is a lightweight material having superior mechanical properties and thermal stability and a promising material for light-weight mirrors for space applications. In this work, the surface of carbon fibre reinforced polymer is electroless nickel-phosphorus plated. The morphologies of the substrate and as-plated surfaces are compared. The surface roughness of the plated surface showed a significant reduction after the plating process. The elemental composition and phase of the as-plated sample are studied. The plated carbon fibre reinforced polymer surface is polished using an elastic tool with a diamond abrasive pad having grit sizes of 45 and 9 μm. The topography and the morphology of the finished surface are analysed for understanding the material removal process. A minimum Ra of 48 nm is obtained on the plated surface after 28 min of polishing. At a finishing rate of 18.17 nm/min, a 91.4% drop in Ra is achieved in comparison to a plated surface.

Tribological behaviour of surface modified carbon-fibre-reinforced polyphenylene sulphide under dry condition

This study presents a direct electrochemical modification technique for incorporating two specific small molecules, phenol, and aniline into carbon fibre (CF) surface. These molecules have a strong hydrogen bonding for polyphenylene sulphide (PPS) and are intended to improve the friction and wear properties of PPS/CF composites. The tribological properties of PPS/CF composites were evaluated using a pin-on-disc. To get a more thorough comprehension of the working conditions of PPS/CF composites, a comparative examination of the composites' tribological characteristics was carried out by modifying the nature of the opposing surface while keeping the sliding speed of the applied force consistent. The results showed that the addition of 10 mM phenol to carbon fibre results in a significant reduction in the coefficient of friction (COF) compared to carbon fibre treated with 50 mM phenol and 6 mM aniline when in contact with a steel counter-face. When sliding against a polymer counter-face, the composites experienced a reduction in the COF due to the formation of a transfer film rich in PPS. Introducing aniline groups to the fibre surface reduced the wear rate by 57.5% to 46% with applied forces of 25 N compared to PPS and unmodified PPS/CF when sliding against the polymer counter-face. This study thoroughly discusses the synergistic process of chemical modification on the tribological performance of PPS/CF. It also analyses the surface microstructures of the worn surfaces of the composites. This study has the potential to provide new insights into the design and development of CF/polymer composites with enhanced friction and wear properties.

Color construction of multi-colored carbon fibers using glucose

Carbon fibers (CFs) have attracted attention in the automotive, aviation, and aerospace industries. However, the coloration of CFs is challenging due to their brittleness, inertness, complexity, and time/energy-intensive processes. Herein, inspired by the naturally grown protrusive nanostructures on the green central surface of peacock back feathers, we report an in-situ self-growing strategy for developing carbon spheres (CSs) on the CFs surface to achieve color tuning. This is achieved via the dynamic growth of CSs using glucose as the feeding material. Combined with the coloration process, the interaction between CSs and CFs promotes stable interfacial forces in integrated molding. This strategy allows the coloring system to continuously vary its color in a designated manner, thereby, endowing it with satisfactory mechanical robustness, acid durability, and light fastness. We anticipate this developed approach can be potentially competitive in the color construction of CFs with multi-colors due to its low-cost manufacturing.

Effect of Ni coating thickness on microstructure and properties of CF/Al composites prepared by vacuum pressure infiltration process

In this paper, Ni coatings with different thickness (∼0.21 μm, ∼0.46 μm, ∼0.65 μm, ∼0.76 μm) were applied on the surface of carbon fiber (CF) by electroless plating process and carbon fiber aluminium matrix (CF/Al) composites were prepared by vacuum pressure infiltration process at 1023 K. The results show that when the coating was relatively thin, the coating was not uniform due to the inconsistent surface activity of CF. When the coating was relatively thick, there was a certain amount of stress inside the coating, which results in poor bonding between the coating and CF. As a result, it was prone to shedding during Al liquid infiltration and a large number of Al–Ni compounds were formed in the matrix. The compounds have a certain fracture brittleness, which is not conducive to improving the tensile properties of the composites. When the thickness of Ni coating was 0.46 ± 0.017 μm, the appropriate diffusion reaction of the coating in the matrix changed the bonding form of the interface from physical bonding to chemical bonding. Under this condition, the strength of CF/Al composites was the highest. It has a tensile strength of 110.58 ± 1.6 MPa, which is approximately 83% higher than that of the pure Al matrix.