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Tn recent years, graphene/polyurethane nanocomposites have attracted much attention due to their superior comprehensive properties. Incorporating graphene or its derivatives into I〉U matrix could significantly improve the physical mechanical, thermal, electromagnetic and other properties, which meets the special requirements of high-performance and multi-functional polymer composites. Tn this paper, the functional modification methods of graphene nanosheets, including covalent modification and non-covalent modification were first introduced. Furthermore, the fabrication processes of graphene/poly urethane nanocomposites, including in-situ polymerization, solution blending, melt blending, aqueous (latex) blending, etc., were briefly introduced. The recent research progress of graphene/poly urethane composites in mechanical, electrical, dielectric, thermal, gas barrier, flame retardant, electromagnetic interference shielding and corrosion resistant properties were all reviewed in detail. The future challenges and development prospects of high-performance graphene/poly urethane nanocomposites were also prospected. [ABSTRACT FROM AUTHOR]

The all-solid-state lithium battery has the advantages of high safety and reliability, high energy density, long cycle life, wide electrochemical window, and good high temperature adaptability. However, the main bottleneck restricting its practical application lies in the interface between the electrode and the solid electrolyte, such as Li dendrites and volume expansion in the anode interface region, as well as structural changes, space charge layer and side reactions in the cathode interface region. Graphene is widely used in the field of electrochemical energy storage due to its special 2D structure, excellent electrical conductivity, thermal conductivity and mechanical properties. In this paper, the authors review the research progress on the modification of electrode/solid electrolyte interface with graphene, and prospect the application of graphene in solid-state batteries. [ABSTRACT FROM AUTHOR]

Fluorescence quenching is widely used in biological detection, environmental detection, and heavy metal detection. Previous studies have shown that Gr is an effective fluorescence quencher which can quench various organic dye coatings. In this paper, the super yellow light-emitting PPV copolymer (super yellow, SY) was used as the fluorescent dye. We study the effect of the position of Gr layers on the fluorescence quenching by preparing four different stacked structures and analyze the quenching mechanism. The results show that the Gr/SY/Gr structure has the best fluorescence quenching efficiency, and the quenching mechanism is dynamic quenching based on electron transfer. This study promotes the application of Gr in biosensors, bioluminescent labeling, environmental pollution detection and other fields. [ABSTRACT FROM AUTHOR]

The wettability of graphene that makes graphene as a functionalized material has attracted widespread attention in the domain of surface engineering. This article starts from the fundamental simulation method for the wettability of graphene, and summarizes the effects on the wettability of graphene which contains defect structures, surface topography, aerial contaminations and so on. Based on the research about the analysis of graphene transparent wettability, the paper expounds the reason why the tendency of transparent wettability in graphene could be generated, and generalizes the research about the graphene transparent wettability. With the two different coating materials which is graphene and graphene oxide, this paper discusses the method to form the superhydrophobic graphene surface. Tn term of research and development status of functional surface wettability of graphene, some key scientific issues that are needed to be solved are proposed in this paper. The future study of wettability of graphene is also prospected in the end. [ABSTRACT FROM AUTHOR]

The wettability of graphene that makes graphene as a functionalized material has attracted widespread attention in the domain of surface engineering. This article starts from the fundamental simulation method for the wettability of graphene, and summarizes the effects on the wettability of graphene which contains defect structures, surface topography, aerial contaminations and so on. Based on the research about the analysis of graphene transparent wettability, the paper expounds the reason why the tendency of transparent wettability in graphene could be generated, and generalizes the research about the graphene transparent wettability. With the two different coating materials which is graphene and graphene oxide, this paper discusses the method to form the superhydrophobic graphene surface. Tn term of research and development status of functional surface wettability of graphene, some key scientific issues that are needed to be solved are proposed in this paper. The future study of wettability of graphene is also prospected in the end. [ABSTRACT FROM AUTHOR]

The contacts and fingers in the traditional high-voltage circuit breakers are all made of copper-tungsten alloy materials by powder metallurgy process at present, and their conductivity and hardness have reached the bottleneck, which cannot meet the demands of increasingly harsh working requirements. Graphene has good electrical conductivity, mechanical properties and high specific surface area. Doped into the traditional coppertungsten alloy, graphene is expected to greatly and simultaneously improve the electrical conductivity and hardness of copper-tungsten electric contacts. Tt has become the main development direction of current electrical contact materials research. Tn this paper, the research progress in strengthening methods of traditional copper-tungsten electric contact materials by using graphene and other reinforcing agents is systematically reviewed, and the strengthening mechanism of graphene on copper-tungsten electric contact materials is explored, so as to provide technical guidance for the development and application of new high strength and high conductivity graphene-reinforced copper-tungsten electric contact materials with new performance and long service life. [ABSTRACT FROM AUTHOR]

In this paper, graphene from inexpensive sucrose is prepared by in-situ growth directly on the Cu flakes, and Cu matrix materials(Cu-MMs) with various in-situ graphene content is fabricated by hot-press sintering. The effect of sucrose content on the phase composition, microstructure and thermal properties of bulk Cu-MMs is studied by XRD, SEM, thermal conductivity (TC) and coefficient of thermal expansion (CTE). Results obtained indicate that after the heat treatment at 800 ℃ for 15 min under the H2/Ar gas flow, the in-situ growth of graphene on the surface of Cu flakes occurs. The graphene exhibits good attachment to Cu matrix and homogenous dispersion, which is beneficial for thermal properties of Cu-MMs. With 0.73 vol% grapheme, the TC of Cu-MMs reaches 339 W/(m·K), which is higher by 19.3% than that of Cu, and meanwhile CTE is far lower than that of Cu from 50 ℃ to 300 ℃. [ABSTRACT FROM AUTHOR]

With the rapid development of the information age, a variety of electronic products have been widely used in our daily and working life. The electromagnetic pollution has become an increasingly serious problem. Absorbing materials with "thin, light, wide, strong" have been widely concerned. Tn this paper, BaF. 0押： graphene and Si()< are mixed by mechanical mixing method to prepare multi--absorbent composite powders. Using waterborne polyurethane as binder, polyamide fabric with multi-absorbent composite coating is prepared by tape casting. The structure, morphology, mechanical and wave absorption properties of the flexible composites are analyzed. The results show that when the absorber component is ().4(BaFei2 O1f)-Graphene)-().6Si()2 and the thickness of the absorbing coatings is 1.2 mm, the sample shows the best micro wave absorption performance with the minimum reflection loss of -14.58 dB, and the bandwidth with reflection loss below -1 0 dB of 0.94 GHz (1 2.91-1 3.58 GHz). Tt has the excellent performance of thin coating, high absorption intensity, wide absorption band and light weight. [ABSTRACT FROM AUTHOR]

Graphene (G)/graphene oxide (GO) has shown promising applications in improving the mechanics and functionality of cement materials with its excellent mechanical, electrical, and thermal conductivity properties. However, these nanomate rials are difficult to disperse in cement-based materials, which limits their practical application in cement-based composites. Tn recent years, researchers have begun to mix fibers with these nanomaterials into cement-based materials, and its dispersion performance has been greatly improved. Tn this paper, the influence of graphene, GO and other fiber mixture on cement-based composite materials is systematically described from five aspects of material dispersion in cement, cement hydration process, mechanical properties, functionality and durability, which has a guiding role in improving the performance of cement-based composite materials in the future. [ABSTRACT FROM AUTHOR]

Tn this paper, natural plant polyphenol-tannic acid (TA) is used as the reducing agent of graphene oxide (GO), and the green reduction and functionalization of GO are realized through the "one--step method0. Subsequently, the TA reduced graphene oxide (RGO) and single-walled carbon nanotubes (SWCNT) are combined to jointly construct a RGO/SWCNT conductive film with a three-dimensional structure. The transparent conductive film (TCF) has good electrical conductivity (when the light transmittance is 75.1 %, the surface resistance is 36.1 f2/sq), low roughness (the roughness of the film is only 5.45 nm), excellent flexibility (after 1 000 cycles of bending, the sheet resistance of the film remains unchanged) and good interfacial adhesion (the adhesion factor of the film is all 二》0.9). The composite film has good performance and can be applied in the field of flexible wearable devices. [ABSTRACT FROM AUTHOR]

Graphene is a nanomaterial composed of two-dimensional mono-crystalline structure with a single atomic layer. It has excellent properties in optics and mechanics, however its hydrophobicity and biological incompatibility limit its applications. In order to solve this problem, the functionalization of graphene has become a research hotspot in recent years. Functionalized graphene, including graphene oxide, graphene polymer composites, angular graphene, graphene, aerogels and super tough graphene, is modified by physicochemical treatment and structure improvement to make the graphene functional. Functionalized graphene has excellent photo- electric properties, including high sensitivity, high responsiveness and high detection degree, etc. It can be used for industrial detection and monitoring, three-dimensional morphology measurement, biomedicine and other neighborhood. In this paper, the properties and preparation methods of functionalized graphene are discussed, the latest progress of functionalized graphene is introduced, and its applications in different devices and its excellent properties are described. Meanwhile, the challenges faced by functional graphene are summarized and prospected. [ABSTRACT FROM AUTHOR]

With the rapid development of communication technology and electronic equipment, electromagnetic pollution has affected the normal operation of electronic equipment and the safety of human life. Therefore, the development of electromagnetic shielding materials is of great scientific significance. In recent years, polymer based carbon nanocomposites have developed rapidly in the field of electromagnetic shielding, showing many excellent properties, which have attracted wide attention in academic cireles. Based on our group's understanding and research in the field of electromagnetic shielding, this paper briefly introduces the principle of electromagnetic shielding and the preparation methods of polymer-based carbon nano composites, with emphasis on the research progress of polymer-based carbon nanocomposites prepared by backfilling method. finally, the future development trend and application of electromagnetic shielding materials are prospected. [ABSTRACT FROM AUTHOR]

Graphene and MXene? as two new two-dimensional materials? have unique structures and properties? such as high conductivity，large specific surface area? light weight, etc., which have been widely concerned and studied in recent years. Tn particular? the research on MXene with graphene like structure is very popular. In this paper? the structure, absorbing performance and research status of the two materials are compared, and the single material, carbon nanotubes, magnetic particles, conductive polymers and carbon fiber composite materials in the field of electromagnetic absorbing are summarized. Tn addition，the absorbing mechanism and design principles of the two materials are extracted. It is expected to provide ideas for the research of "thin，light， soft? wide" new electromagnetic absorption materials based on two-dimensional materials. [ABSTRACT FROM AUTHOR]

Barrier materials are becoming more and more important in packaging and protection applications, while common barrier polymers, such as polyethylene, polypropylene, polyvinyl ailcohol, etc., generally have the disadvarntages of low mechanical strength and poor barrier to small molecules. Therefore, the development of high barrier materials has become a new research direction. Graphene is a two-dimensional layered nano-filler with large aspect ratio and specific surface area, which can build a stable filler network and form a tortuo us mo lecular movement path in the nrntrix ma1terial. There are a brge number of oxygen-conwining functional groups on the surface of graphene oxide, which can form a strong interaction with polar molecules, so ats to inhibit the migration of small molecules and improve the barrier properties of the composites. In this paper, the barrier properties of graphene and its derivatives were summarized, then the modification of graphene and the prepara tion methods of graphene nanocomposites were introduced, and the advantages and disadvantilges of different modification and preparation methods were compared. Fin

Formaldehyde is a typical indoor pollution gas, which harms people's health seriously. ZnSnO3 is a ternary metal oxide with a perovskite structure and is widely used in gas sensing materials.In this paper, different rGO- doped ZnSnO3 composites were successfully synthesized by one-step hydro thermal method. XRD, FTIR, SEM, TGA, XPS and BET methods were adopted to characterize the structure, morphology, thermal stability, chemical composition, and specific surface area of composite materials, and the gassensing properties to different target gases, such as ethanol, acetone, ammonia, Benzene and formaldehyde, were also investigated. The experimental results showed that ther GO-doped ZnSnO3 could effectively improvet he gas sensitivity of ZnSnO3. Among them, the 4%rGO/ZnSnO3 composite had the highest sensitivity to 3 0×10-6 formaldehyde gas (38.9), fast response recovery time (112s,15s)and good selectivity and stability [ABSTRACT FROM AUTHOR]

Due to its unique two-dimensional lamella structure, graphene exhibits excellent electrical and mechanical properties, which has made it become a new hotspot in material research, bringing people a rich imagination. In this paper, based on the principle and technical characteristics as well as microstructure, various preparation techniques of graphene were compared. The microstructure characterization techniques and main properties of graphene were summarized. In view of the current bottleneck problem in graphene application, the modification methods of non-covalent and covalent bonds of graphene were described. The applications of graphene in batteries, energy storage, coating, medicine, sensors and additives, etc. were also reviewed. Finally, the future development direction of graphene was boldly predicted. [ABSTRACT FROM AUTHOR]

Graphene is considered to be an ideal reinforcement because of its excellent properties. It is also prone to agglomeration, which reduces the properties of materials. In this paper, K2FeO4 was transformed to Fe3O4 by graphite and anchored on the graphite sheet by high energy ball milling in order to increase the shear force of grinding ball on graphite and then strip graphene from graphite. Dispersed Fe-based/graphene nanocomposites were obtained by controlling milling time. The composite powders were characterized by SEM, XRD and infrared spectroscopy. The results show that the Fe-based/graphene nanocomposites achieved by ball milling for 2 hours exhibited the best dispersibility and the number of graphene lamellae was low. [ABSTRACT FROM AUTHOR]

Graphene has excellent material properties and a wide range of applications. The preparation technology of graphene-based materials has been highly valued. The key preparation techniques of graphene-based materials, such as surface functionalization, gamma ray irradiation, self-assembly, template synthesis, 3 D printing and powder metallurgy, were introduced in this paper. The technical principles of each process, preparation techniques and advantages and disadvantages of the resulting product were described. In order to better realize the application value of graphene-based materials, the next research was prospected. [ABSTRACT FROM AUTHOR]

Low thermal conductivity is a major disadvantage that limits the practical application of energy storage materials. Graphene with highly thermal conductivity can be used as a thermal conductive filler to effectively improve the thermal conductivity of energy storage materials. In this paper, the thermal conductivity and internal interaction of graphene/pentaerythritol (GE/PE) solid-solid phase change composites were simulated by reverse non-equilibrium molecular dynamics method and Materials Studio software with graphene (GE) mass fraction of 0.5%, 1 %, 1.5%, 2 %, 2.5% and 3%.The results show that the addition of graphene could effectively improve the thermal conductivity of pentaerythritol. With the increase of GE mass fraction, the thermal conductivity, interfacial thermal conductivity and interaction energy of GE/PE composite phase change material were gradually increased, and the trend amplitude was consistent. The overall increase in thermal conductivity was attributed t o the change of graphene structure. It could provide guidance for experimental research on graphene to improve thermal conductivity of pentaerythritol. [ABSTRACT FROM AUTHOR]

In this paper, a porous silicon powder material and a porous silicon/graphene composite material were prepared by using Al-20Si alloy as a raw material, and used as a negative electrode material for lithium ion batteries. A porous silicon powder material was prepared by etching an alloy with hydrochloric acid. Porous silicon/graphene composites were prepared by ultrasonically adding different amounts of graphene (0, 5%, 10%, 15%, 20%, 25%) to a silicon-based material, respectively. The experimental results show that the addition of 10% graphene to the porous silicon-based material had the best electrochemical performance. The first charge and discharge capacity was 2 552 mAh/g, and the charge and discharge capacity was finally stabilized at 540 mAh/g. The first charge and discharge efficiency was 78.5%. After the five cycles, the efficiency during subsequent charging and discharging was maintained at about 98%. When the amount of added graphene exceeded 10%, the performance gradually decreased as the amount of addition increased. The addition of graphene reduced the charge-discharge specific capacity but increased the cycling stability of the silicon. [ABSTRACT FROM AUTHOR]

With the development of electronics？ spaceflight and aviation, the integrated circuit develops rapidly, but it is often accompanied by the problem of heat dissipation ？ which affects the efficiency and the life of instruments. Considering the weight, corrosion resistance？ processing technology and cost？ polymer composites are the most promising materials for thermal conductivity. However, the inherent thermal conductivity of polymers is very low, so improving the thermal conductivity of polymers is very important for their applications in these fields ？ which has become a very important research topic in the past two decades. Tn this review paper, the following two aspects were mainly introduced. The micro thermal conductivity mechanism of polymers was analyzed and summarized from three aspects of molecular chain morphology ？ chain structure and inter-chain coupling. The main research progress in the thermal conductivity of graphene-filled polymer nanocomposites in recent years and the research challenges in the future were highlighted. [ABSTRACT FROM AUTHOR]

Tr ithis paper, the growth of graphene on sapphire substrate was studied by the experimental preparation and simulation using chemical vapor deposition (CVD) method 􀀀 which focused on the effect of substrate surface morphology and growth temperature. The microstructure of graphene was investigated by atomic force microscope (AFM),X-ray diffraction (XRD) ？ field emission scanning electron microscope (FESEM) ？ Raman spectroscopy (Raman),and high resolution transmission electron microscope (HRTEM) respectively. The simulation results indicated that hydrogen had an important influence on the surface morphology of the substrate. Under the action of H atom ? the Al-() bond was elongated by 51.42% ? which was almost fractured ？ and it affected the surface roughness of the sapphire substrate. Tt was found that H had an etching effect on the surface of sapphire substrate？ and the surface roughness Ra of the etched sapphire substrate became larger, which made it difficult to grow graphene. When the growth temperature increased 􀀀 the quality of the graphene also became better. [ABSTRACT FROM AUTHOR]