Showing papers on "Surface modification published in 2016"
TL;DR: It is shown that covalent aryl diazonium functionalization suppresses the chemical degradation of exfoliated BP even after three weeks of ambient exposure, and thus improves its prospects for nanoelectronic applications.
Abstract: Functionalization of atomically thin nanomaterials enables the tailoring of their chemical, optical and electronic properties. Exfoliated black phosphorus (BP)-a layered two-dimensional semiconductor-exhibits favourable charge-carrier mobility, tunable bandgap and highly anisotropic properties, but it is chemically reactive and degrades rapidly in ambient conditions. Here we show that covalent aryl diazonium functionalization suppresses the chemical degradation of exfoliated BP even after three weeks of ambient exposure. This chemical modification scheme spontaneously forms phosphorus-carbon bonds, has a reaction rate sensitive to the aryl diazonium substituent and alters the electronic properties of exfoliated BP, ultimately yielding a strong, tunable p-type doping that simultaneously improves the field-effect transistor mobility and on/off current ratio. This chemical functionalization pathway controllably modifies the properties of exfoliated BP, and thus improves its prospects for nanoelectronic applications.
669 citations
TL;DR: The processing of carbon nanotube, graphene, and clay montmorillonite platelet are reviewed as potential nanofillers to form nanocomposites to review the challenges and future outlook for nanofilled polymeric composites.
Abstract: Nanofilled polymeric matrices have demonstrated remarkable mechanical, electrical, and thermal properties. In this article we review the processing of carbon nanotube, graphene, and clay montmorillonite platelet as potential nanofillers to form nanocomposites. The various functionalization techniques of modifying the nanofillers to enable interaction with polymers are summarized. The importance of filler dispersion in the polymeric matrix is highlighted. Finally, the challenges and future outlook for nanofilled polymeric composites are presented.
536 citations
TL;DR: It is demonstrated that macrophages cultured on high surface wettability materials produce an anti-inflammatory microenvironment, and this property may be used to improve the healing response to biomaterials.
434 citations
TL;DR: In this paper, the authors highlight the interfacial and interparticle CTs under the bandgap excitation of TiO2 particles, visible light-induced photochemical processes via either dye-sensitization or ligand-to-metal CTs at surface modified TiO 2 particles, and the applications of the photoprocesses to pollutant degradation and simultaneous hydrogen production.
Abstract: High efficiency solar photocatalysis requires an effective separation of photogenerated charge carriers and their rapid transport to the semiconductor interface. The mechanisms and kinetics of charge separation and interfacial/interparticle charge transfers (CT) are significantly influenced by both the bulk and surface properties of the semiconductor. The surface properties are particularly important because the photocatalysis should be driven by the interfacial CT. The most popular and the most investigated semiconductor photocatalyst is based on bare and modified TiO2. This article highlights the interfacial and interparticle CTs under the bandgap excitation of TiO2 particles, visible light-induced photochemical processes via either dye-sensitization or ligand-to-metal CTs at surface modified TiO2 particles, and the applications of the photo-processes to pollutant degradation and simultaneous hydrogen production. While a variety of surface modification techniques using various nanomaterials and chemical reagents have been developed and tested so far, their effects are very diverse depending on the characteristics of the applied photocatalytic systems and even contradictory in some cases. Better understanding of how the modification influences the photoinduced CT events in semiconductors is required, particularly for designing hybrid photocatalysts with controlled CTs, which is sought-after for practical applications of photocatalysis.
415 citations
TL;DR: In this paper, the TiO2 nanoparticles were directly anchored on the surface of poly(vinylidene fluoride) (PVDF) membrane, making the intrinsic hydrophobic polymer membrane become hydrophilic, what's more, the mussel inspired method was modified by introducing a silane coupling agent KH550, the ability to bind nanoparticles was retained and the as-prepared membrane turn from a common hydrophic state to superhydrophilic state.
400 citations
TL;DR: In this paper, the authors summarize recent progress in doping and surface functionalization of C-dots for improving their functionality, and offer insight into controlling the properties of carbon nanodots for a variety of applications.
Abstract: Distinct from conventional carbon nanostructures, such as fullerene, graphene, and carbon nanotubes, carbon nanodots (C-dots) exhibit unique properties such as strong fluorescence, high photostability, chemical inertness, low toxicity, and biocompatibility. Various synthesis routes for C-dots have been developed in the last few years, and now intense research efforts have been focused on improving their functionality. In this aspect, doping and surface functionalization are two major ways to control the chemical, optical, and electrical properties of C-dots. Doping introduces atomic impurities into C-dots to modulate their electronic structure, and surface functionalization modifies the C-dot surface with functional molecules or polymers. In this review, we summarize recent progress in doping and surface functionalization of C-dots for improving their functionality, and offer insight into controlling the properties of C-dots for a variety of applications ranging from biomedicine to optoelectronics to energy.
340 citations
TL;DR: This work demonstrates the improvement of gas-sensing performance of large-area tungsten disulfide (WS2) nanosheets through surface functionalization using Ag nanowires (NWs) to improve 2D TMDC gas sensors.
Abstract: Semiconducting two-dimensional (2D) transition metal dichalcogenides (TMDCs) are promising gas-sensing materials due to their large surface-to-volume ratio. However, their poor gas-sensing performance resulting from the low response, incomplete recovery, and insufficient selectivity hinders the realization of high-performance 2D TMDC gas sensors. Here, we demonstrate the improvement of gas-sensing performance of large-area tungsten disulfide (WS2) nanosheets through surface functionalization using Ag nanowires (NWs). Large-area WS2 nanosheets were synthesized through atomic layer deposition of WO3 followed by sulfurization. The pristine WS2 gas sensors exhibited a significant response to acetone and NO2 but an incomplete recovery in the case of NO2 sensing. After AgNW functionalization, the WS2 gas sensor showed dramatically improved response (667%) and recovery upon NO2 exposure. Our results establish that the proposed method is a promising strategy to improve 2D TMDC gas sensors.
315 citations
TL;DR: The review focuses on the method of nanoparticle formation (self-assembled, physical or chemical cross-linked) when engineering polysaccharide-based nanoparticles for theranostic nanomedicine.
300 citations
TL;DR: The photothermal conversion effect is demonstrated for the first time on the nanoCOF layers upon exposure to near infrared light, providing convincing evidence for potential use in phototherapy.
Abstract: An approach to transforming amorphous organic networks into crystalline covalent organic frameworks (COFs) with retention of the colloidal nanosize and uniform morphology is presented. Specifically, Fe3O4 nanoclusters are encapsulated by a disordering polyimine network via the Schiff-base reaction. The formed imine bonds could be reconstructed under thermodynamic control to reform the polyimine networks into imine-linked COFs in situ. Such a core–shell microsphere exhibits the uniform size and spherical shape, controllable COF shell thickness, accessible surface modification, and improved solution dispersibility as well as maintenance of high surface area, periodic micropores, and superior magnetic responsiveness. Additionally, the photothermal conversion effect is demonstrated for the first time on the nanoCOF layers upon exposure to near infrared light, providing convincing evidence for potential use in phototherapy.
279 citations
TL;DR: Representative approaches to coating the surface with various functional groups, and strategies for conjugating specific materials onto the surface of carbon dots for functional modification via covalent bonds, electrostatic interactions and hydrogen bonds are highlighted.
Abstract: Carbon dots have attracted a great deal of attention because of their high performance, cheap and facile preparation, and potential applications in a wide area. In order to broaden their applications, especially to meet specific requirements, surface engineering, including tailoring surface functional group coating and subsequent chemical modification as required, is an effective strategy for further functionalization of carbon dots. In this article, representative approaches to coating the surface with various functional groups, and strategies for conjugating specific materials onto the surface of carbon dots for functional modification via covalent bonds, electrostatic interactions and hydrogen bonds are highlighted, as well as the results from explorations of their various applications in target modulated sensing, accurate drug delivery and bioimaging at high resolution.
270 citations
TL;DR: In this paper, a top-down strategy is established to construct hollow MOFs via synergistic etching and surface functionalization by using phenolic acid, and the modified MOFs are simultaneously coated by metal-phenolic films, which endows the added functionality of responding to near infrared irradiation to produce heat for potential photothermal therapy applications.
Abstract: The rational design and engineering of metal–organic framework (MOF) crystals with hollow features has been used for various applications. Here, a top-down strategy is established to construct hollow MOFs via synergistic etching and surface functionalization by using phenolic acid. The macrosized cavities are created inside various types of MOFs without destroying the parent crystalline framework, as evidenced by electron microscopy and X-ray diffraction. The modified MOFs are simultaneously coated by metal–phenolic films. This coating endows the MOFs with the additional functionality of responding to near infrared irradiation to produce heat for potential photothermal therapy applications.
TL;DR: In this paper, three kinds of Co3O4 catalysts with different concentrations of surface oxygen vacancies were successfully synthesized through a solvothermal and subsequent thermolysis method, and they exhibited the best performance for formaldehyde oxidation due to their larger specific surface area, higher low-temperature reducibility and abundant active surface oxygen species.
TL;DR: In this article, the effects of incorporation of two different shapes functionalization fullerene C60 (FC60) and functionalization graphene (FG), into the polymer matrix on the tribological and anti-corrosion performances of epoxy coating were investigated.
Abstract: This study investigated the effects of incorporation of two different shapes functionalization fullerene C60 (FC60) and functionalization graphene (FG), into the polymer matrix on the tribological and anti-corrosion performances of epoxy coating. The structural and morphological characterization was examined using Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, transmission electron microscopy and scanning electron microscopy. It was found that the functional groups had been grafted on the surface of C60 and G. The tribological and anti-corrosion results indicated that composite coatings showed a lower friction coefficient, wear traces area and higher anti-corrosion in comparison with neat epoxy, owing to the balance of reinforcement, lubrication and barrier properties of nanofillers and cracks generated by them, and optimal additive concentration of FC60 and FG both were 0.5 wt.%. Furthermore, this work opens up that FC60/EP coatings exhibited better tribological performance but worse corrosion resistance ability compared with FG/EP coatings due to the different shapes of nanofillers. Different tribological and anti-corrosion mechanisms were analyzed in details.
TL;DR: In this paper, a superhydrophobic coating (SHPC) on the Al surface was fabricated via a simple and cost effective method using anodization in sulfuric acid electrolyte followed by surface modification with inexpensive myristic acid.
TL;DR: In this paper, the authors introduced the method of using self-assembled monolayers (SAMs) to functionalize surfaces for the enhancement of TENGs' output, which revealed their direct correlation.
Abstract: Triboelectric nanogenerators (TENGs) have been invented as a new technology for harvesting mechanical energy, with enormous advantages. One of the major themes in their development is the improvement of the power output, which is fundamentally determined by the triboelectric charge density. Besides the demonstrated physical surface engineering methods to enhance this density, chemical surface functionalization to modify the surface potential could be a more effective and direct approach. In this paper, we introduced the method of using self-assembled monolayers (SAMs) to functionalize surfaces for the enhancement of TENGs' output. By using thiol molecules with different head groups to functionalize Au surfaces, the influence of head groups on both the surface potential and the triboelectric charge density was systematically studied, which reveals their direct correlation. With amine as the head group, the TENG's output power is enhanced by ∼4 times. By using silane-SAMs with an amine head group to modify the silica surface, this approach is also demonstrated for insulating triboelectric layers in TENGs. This research provides an important route for the future research on improving TENGs' output through materials optimization.
TL;DR: In this paper, a critical review represents an extensive overview of the synthesis of a variety of g-C3N4 nanostructured materials with a controllable structure, morphology and surface modification for superior electronic properties.
Abstract: Graphitic carbon nitride (g-C3N4) is gaining more and more importance as a photocatalytic material due to its promising electronic band structure and high thermal and chemical stability. Very recently, a variety of nanostructured g-C3N4 photocatalysts with varying shapes, sizes, morphologies and electronic band structures have been reported for application in photocatalytic research. This critical review represents an extensive overview of the synthesis of a variety of g-C3N4 nanostructured materials with a controllable structure, morphology and surface modification for superior electronic properties. This article highlights the design of efficient photocatalysts for the splitting of water into hydrogen gas using solar energy. Finally, in the summary and outlook, this article highlights the ongoing challenges and opportunities of g-C3N4. It is also hoped that this review will stimulate further investigation and will open up new possibilities to develop new hybrid g-C3N4 materials with new and exciting applications.
TL;DR: A review of carbon nanotubes functionalization can be found in this article, where the authors highlight recent developments in the functionalization of CNTs and their applications and highlight the potential of functionalizing CNT to improve chemical compatibility and dissolution properties.
Abstract: Carbon nanotubes (CNT)s show exceptional one-dimensional π-electron conjugation, mechanical strength, high chemical and thermal stability, which make them very attractive for use in many applications. CNTs intrinsically tend to hold together as ropes and bundles due to van der Waals interactions. The prevention of such behavior has been investigated by testing a variety of surface modification methods. The functionalized CNTs present enhanced properties enabling facile production of novel nanomaterials and nanodevices. The functionalization of CNTs could improve their chemical compatibility and dissolution properties, which would enable both a wider characterization and consequent chemical reactivity. This review aims to provide a brief synopsis of CNT functionalization and highlights recent developments in the functionalization of CNTs and their applications.
TL;DR: The findings suggest that functionalization of two-dimensional MoS2 using organic thiols may not yield covalently or datively tethered functionalities, rather, in this instance, they yield physisorbed disulfides that are easily removed.
Abstract: Two-dimensional layered transition metal dichalcogenides (TMDs) have attracted great interest owing to their unique properties and a wide array of potential applications. However, due to their inert nature, pristine TMDs are very challenging to functionalize. We demonstrate a general route to functionalize exfoliated 2H-MoS2 with cysteine. Critically, MoS2 was found to be facilitating the oxidation of the thiol cysteine to the disulfide cystine during functionalization. The resulting cystine was physisorbed on MoS2 rather than coordinated as a thiol (cysteine) filling S-vacancies in the 2H-MoS2 surface, as originally conceived. These observations were found to be true for other organic thiols and indeed other TMDs. Our findings suggest that functionalization of two-dimensional MoS2 using organic thiols may not yield covalently or datively tethered functionalities, rather, in this instance, they yield physisorbed disulfides that are easily removed.
TL;DR: In this paper, the application of beneficial physico-chemical properties of ZnO nanostructures for the detection of wide range of biological compounds is highlighted for medical diagnostics require accurate, fast and inexpensive biosensors, the advantages inherent optical methods of detection are considered.
Abstract: This review article highlights the application of beneficial physico-chemical properties of ZnO nanostructures for the detection of wide range of biological compounds. As the medical diagnostics require accurate, fast and inexpensive biosensors, the advantages inherent optical methods of detection are considered. The crucial points of the immobilization process, responsible for biosensor performance (biomolecule adsorption, surface properties, surface defects role, surface functionalization etc.) along with the interaction mechanism between biomolecules and ZnO are disclosed. The latest achievements in surface plasmon resonance (SPR), surface enhanced Raman spectroscopy (SERS) and photoluminescence based biosensors along with novel trends in the development of ZnO biosensor platform are presented.
TL;DR: Investigation of the use of an extrusion-based additive manufacturing system to produce poly(ε-caprolactone) (PCL)/pristine graphene scaffolds for bone tissue applications and the influence of chemical surface modification on their biological behaviour shows that the addition of pristine graphene had a positive impact on cell viability and proliferation, and that surface modification leads to improved cell response.
Abstract: Scaffolds are physical substrates for cell attachment, proliferation, and differentiation, ultimately leading to the regeneration of tissues. They must be designed according to specific biomechanical requirements, i.e., certain standards in terms of mechanical properties, surface characteristics, porosity, degradability, and biocompatibility. The optimal design of a scaffold for a specific tissue strongly depends on both materials and manufacturing processes, as well as surface treatment. Polymeric scaffolds reinforced with electro-active particles could play a key role in tissue engineering by modulating cell proliferation and differentiation. This paper investigates the use of an extrusion-based additive manufacturing system to produce poly(e-caprolactone) (PCL)/pristine graphene scaffolds for bone tissue applications and the influence of chemical surface modification on their biological behaviour. Scaffolds with the same architecture but different concentrations of pristine graphene were evaluated from surface property and biological points of view. Results show that the addition of pristine graphene had a positive impact on cell viability and proliferation, and that surface modification leads to improved cell response.
TL;DR: This work demonstrates how photoredox-mediated C(sp3 )-H activation through radical translocation can be combined with asymmetric catalysis to provide a C-C bond-formation product with high enantioselectivity.
Abstract: This work demonstrates how photoredox-mediated C(sp3)−H activation through radical translocation can be combined with asymmetric catalysis. Upon irradiation with visible light, α,β-unsaturated N-acylpyrazoles react with N-alkoxyphthalimides in the presence of a rhodium-based chiral Lewis acid catalyst and the photosensitizer fac-[Ir(ppy)3] to provide a C−C bond-formation product with high enantioselectivity (up to 97 % ee) and, where applicable, with some diastereoselectivity (3.0:1 d.r.). Mechanistically, the synthetic strategy exploits a radical translocation (1,5-hydrogen transfer) from an oxygen-centered to a carbon-centered radical with a subsequent stereocontrolled radical alkene addition.
TL;DR: This work makes use of the lone pair electrons found in most of 2D metal chalcogenides and reports a functionalization method via a Lewis acid-base reaction that does not alter the host structure and fabricate planar p-n junctions on 2D InSe with improved rectification and photovoltaic properties.
Abstract: Precise control of the electronic surface states of two-dimensional (2D) materials could improve their versatility and widen their applicability in electronics and sensing. To this end, chemical surface functionalization has been used to adjust the electronic properties of 2D materials. So far, however, chemical functionalization has relied on lattice defects and physisorption methods that inevitably modify the topological characteristics of the atomic layers. Here we make use of the lone pair electrons found in most of 2D metal chalcogenides and report a functionalization method via a Lewis acid-base reaction that does not alter the host structure. Atomic layers of n-type InSe react with Ti(4+) to form planar p-type [Ti(4+)n(InSe)] coordination complexes. Using this strategy, we fabricate planar p-n junctions on 2D InSe with improved rectification and photovoltaic properties, without requiring heterostructure growth procedures or device fabrication processes. We also show that this functionalization approach works with other Lewis acids (such as B(3+), Al(3+) and Sn(4+)) and can be applied to other 2D materials (for example MoS2, MoSe2). Finally, we show that it is possible to use Lewis acid-base chemistry as a bridge to connect molecules to 2D atomic layers and fabricate a proof-of-principle dye-sensitized photosensing device.
TL;DR: In this paper, the authors investigated thiolated polyethylene glycol (HS-PEG) as a stabilizing ligand during AuNP catalytic reduction of 4-nitrophenol.
Abstract: Gold nanoparticles (AuNPs) have received considerable interest owing to their unique properties and applications in catalysis. One of the major challenges for colloidal nanoparticles in catalysis is the limited stability and resulting aggregation. Nanoparticle functionalization with ligands or polymers is a common strategy to improve the colloidal stability, which in turn blocks the reactive surface sites and eliminates catalytic activity. Here, we investigate thiolated polyethylene glycol (HS-PEG) as a stabilizing ligand during AuNP catalytic reduction of 4-nitrophenol. We show a direct relationship between the chain length and packing density of HS-PEG with respect to AuNP catalytic activity. High surface coverage of low molecular weight HS-PEG (1 kDa) completely inhibited the catalytic activity of AuNPs. Increasing HS-PEG molecular weight and decreasing surface coverage was found to correlate directly with increasing rate constants and decreasing induction time. Time-resolved UV–vis absorbance spectros...
TL;DR: In this paper, the role of surface termination on the dielectric and optical properties of Ti3C2T2 (T = F, O, OH) MXene is studied using first-principles density functional theory.
Abstract: Role of surface termination on the dielectric and optical properties of Ti3C2T2 (T = F, O, OH) MXene is studied using first-principles density functional theory. The results show that the surface functionalization has a significant impact on the optical properties of the MXene. For example, in the visible range of the spectrum, the oxidized sample shows larger absorption, whereas surface fluorination results in weaker absorption as compared to pristine MXene. In the ultraviolet energy range, all functional groups lead to the enhancement of both absorption and reflectivity of the material. Dielectric properties of MXene are also sensitive to the surface functionalization. Our findings demonstrate the importance of surface termination on the optical properties of the MXene.
TL;DR: The current work presents an important concept toward the application of nanomaterial-based FET sensors for biochemical sensing in physiological environments and thus could lead to powerful tools for basic research and healthcare.
Abstract: Nanomaterial-based field-effect transistor (FET) sensors are capable of label-free real-time chemical and biological detection with high sensitivity and spatial resolution, although direct measurements in high–ionic-strength physiological solutions remain challenging due to the Debye screening effect. Recently, we demonstrated a general strategy to overcome this challenge by incorporating a biomolecule-permeable polymer layer on the surface of silicon nanowire FET sensors. The permeable polymer layer can increase the effective screening length immediately adjacent to the device surface and thereby enable real-time detection of biomolecules in high–ionic-strength solutions. Here, we describe studies demonstrating both the generality of this concept and application to specific protein detection using graphene FET sensors. Concentration-dependent measurements made with polyethylene glycol (PEG)-modified graphene devices exhibited real-time reversible detection of prostate specific antigen (PSA) from 1 to 1,000 nM in 100 mM phosphate buffer. In addition, comodification of graphene devices with PEG and DNA aptamers yielded specific irreversible binding and detection of PSA in pH 7.4 1x PBS solutions, whereas control experiments with proteins that do not bind to the aptamer showed smaller reversible signals. In addition, the active aptamer receptor of the modified graphene devices could be regenerated to yield multiuse selective PSA sensing under physiological conditions. The current work presents an important concept toward the application of nanomaterial-based FET sensors for biochemical sensing in physiological environments and thus could lead to powerful tools for basic research and healthcare.
TL;DR: In this article, the effect of severe shot peening on microstructural and mechanical properties of 316L stainless steel, which is widely used in biomedical, food preparation, structural and marine applications, was evaluated in terms of morphological and structural features, defect density, grain size, phase transformation, surface topography, surface wettability, residual stresses and microhardness.
TL;DR: This critical review of recent developments in the methods of preparing Au@ MNPs, surface functionalization and their application in analytical sensing and biomedicine highlights some of the remaining major challenges, as well as the lessons learnt when working with Au@MNPs.
TL;DR: This work proves covalent nanoparticles-polymer bond formation by liquid NMR after dissolution of the functionalized MOF under mild conditions and estimates the amount of covalently attached polymer by UV–vis spectroscopy.
Abstract: Selective functionalization of the external surface of porous nanoparticles is of great interest for numerous potential applications in the field of nanotechnology. Regarding metal–organic frameworks (MOFs), few methods for such modifications have been reported in the literature. Herein, we focus on the covalent attachment of functional polymers on the external surface of MIL-100(Fe) nanoparticles in order to implement properties such as increased chemical and colloidal stability or dye-labeling for the investigation of the particles by fluorescence based techniques. We prove covalent nanoparticles-polymer bond formation by liquid NMR after dissolution of the functionalized MOF under mild conditions and estimate the amount of covalently attached polymer by UV–vis spectroscopy. The functionalization of the MOF nanoparticles with fluorescently labeled polymers enables the investigation of nanoparticle uptake into tumor cells by fluorescence microscopy. Furthermore, the influence of the polymer shell on the ...
TL;DR: The multifunctionality of the nanofilm coating is demonstrated by both top-down and bottom-up micro-/nanoscale interfacial engineering, including surface modification, all-water-based photo/electron-beam lithography, and electroless deposition.
Abstract: 2D nanofilms assembled by pure protein with a macroscopic area and multiple functions can be directly formed at the air/water interface or at the solid surface at a timescale of several minutes. The multifunctionality of the nanofilm coating is demonstrated by both top-down and bottom-up micro-/nanoscale interfacial engineering, including surface modification, all-water-based photo/electron-beam lithography, and electroless deposition.
TL;DR: In this article, the strategy of surface functionalization of graphene, with either soft matters (e.g., organics, molecular linkers, proteins) or solid inorganic matters, holds the key to enabling the fabrication of high performance compositors.
Abstract: Graphene, including pristine graphene and its analogues of graphene oxide and reduced graphene oxide, is revolutionizing the way we design high performance devices, particularly in the areas of sustainable energy and environmental technologies. From environmental remediation and sensing to energy conversions and storage, there are many successful cases of graphene applications. Instead of being a standalone working material, graphene is almost always coupled with another active material as a composite. With its high surface-to-bulk ratio, efficient heat transfer, and electron conduction, the interfacing with graphene not only helps to overcome such limitations in the bare working material but actually accentuates them. To achieve this, the strategy of surface functionalization of graphene, with either soft matters (e.g., organics, molecular linkers, proteins) or solid inorganic matters (e.g., metal nanoparticles, oxide semiconductors), holds the key to enabling the fabrication of high performance composit...