Applications of graphene-based materials in environmental protection and detection

Many efficient adsorbents and sensors based on graphene and functionalized graphene have been constructed for the removal and detection of environmental pollutants due to its unique physicochemical properties. In this article, recent research achievements are reviewed on the application of graphene-based materials in the environmental protection and detection. For environmental protection, modified graphene can adsorb heavy metal ions in a high efficiency and selectivity, and thus reduces them to metals for recycling. High adsorption capacity of graphene-based materials to kinds of organic pollutants in water was also presented. Several graphene-based sensors with high limit of detection were reported to detect heavy metal ions, toxic gases and organic pollutants in environment. Finally, a perspective on the future challenge of adsorbents and detection devices based on graphene is given.     

石墨烯/无机纳米粒子复合材料的制备及其在生物医学领域的应用

石墨烯以独特的结构和优异的性能一经问世就引起了大范围的研究热潮,随着研究的深入,石墨烯/无机纳米粒子复合材料也成为了材料研究领域的新热点.生物医学领域是石墨烯/无机纳米粒子复合材料的重要研究方向.简述了当下石墨烯/无机纳米粒子复合材料的几种制备方法,重点介绍了其在生物医学领域的应用进展.     

A review on hybridization modification of graphene and its polymer nanocomposites

Recently,graphene has attracted numerous interests from both fundamental and applied fields due to its excellent mechanical,thermal,electrical conductivity and other novel properties.This review gives an overview of recent progress on hybridization modifications of graphene with carbon nanomaterials.Some example applications of graphene-based nanohybrids in polymer composites,optical and conducting materials,high performance electrolyte materials and as well as other functional materials are summarized and discussed.     

石墨烯基TiO_2复合材料的表征及其可见光催化活性研究

以氧化石墨烯与石墨烯为碳源,在熔盐介质中与钛粉反应原位生成石墨烯基TiC中间产物,并通过后续控制氧化制得石墨烯基TiO_2复合光催化剂,结合FTIR、XRD、Raman、SEM等手段,对两种石墨烯材料的结构及形貌差异进行表征,并分析了其对所制复合材料结构、形貌及可见光催化活性的影响。结果表明,所制复合材料仍保持碳源的层片状结构,TiC和TiO_2颗粒均匀包覆在碳源表面;以石墨烯为碳源更有利于表面原位生成TiC晶粒的生长,其晶体结构更为完善;两种结构的石墨烯基TiO_2复合材料均对目标污染物亚甲基蓝有较强的吸附能力和可见光降解能力。     

石墨烯铝基复合材料超声辅助微铣削工艺研究

超声辅助微铣削作为一种新兴复合加工技术,在加工硬脆材料和复合材料中具有独特的优势.针对石墨烯铝基复合材料在工业应用中存在难加工、加工精度要求高、加工效率低等问题,本文以纯铝及石墨烯铝基复合材料为研究对象,对不同配比的石墨烯铝基复合材料进行了超声辅助微铣削实验.通过正交实验分析石墨烯含量、每齿进给量以及超声振幅对铣削力和加工表面粗糙度的影响,从而确定石墨烯铝基复合材料在超声辅助微铣削下的最佳工艺参数.实验结果表明,当每齿进给量为1 μm/z,超声振幅为3.05 μm时,石墨烯铝基复合材料的加工性能最优.      

Preparation and supercapacitor performance of assembled graphene fiber and foam

Graphene-based materials have been full of vigor and tremendous potentiality for application in supercapacitors due to its variety of unique properties such as electronic properties, simple synthesis, etc. In developing new macroscopic nanostructured graphene materials for supercapacitors, considerable efforts have been made by the scientist including our research group. In this account, we describe our development of the construction of the assembled graphene especially fiber and foam, which have great potential in addressing the challenges in the synthesis of graphene-based electrode materials for supercapacitors. As the supercapacitors are reviewed in this article, they are accordant with the rapid development of flexible, lightweight, and wearable-electronic devices, overcoming the major some drawbacks of conventional bulk supercapacitors. We hope that this summary will benefit the further research of graphene-based materials for the applications in electrochemical energy storage devices and beyond.     

Nonlinear optical properties of graphene-based materials

Graphene,a two-dimensional carbon atom sheet,has attracted tremendous attention and research interest because of its exceptional physical properties.Graphene has high mobility and optical transparency,in addition to flexibility,robustness and environmental stability.The main focus so far has been on fundamental physics and electronic devices.However,because the linear dispersion of the Dirac electrons enables ultrawideband tunability,we believe its true potential lies in photonics and optoelectronics.In this review,we introduce recent advances in the nonlinear optical properties of graphene-based materials.The rise of graphene in nonlinear optics is shown by several recent results,ranging from saturable absorbers and the four-wave mixing effect to giant two-photon absorption,reverse saturable absorption and optical limiting.The relevant forms of the graphene-based materials include pure graphene,graphene oxide and graphene hybrids.     

Graphene meets biology

Graphene features a shining star in the material sciences since its discovery in 2004. Biomedical application of graphene-family materials has been driven recently. In this paper, we overviewed the cutting-edge research in the biomedical application of graphene-based biomaterials, such as bio-sensing and bio-imaging, drug/gene delivery and scaffold for tissue engineering. We emphasized on the effect of graphene substrates on cellular behaviors of adhesion, proliferation~ and differentiation. The develop- ment of three-dimensional scaffolds based on graphene- based nanomaterials and the potential of these constructs in tissue engineering are discussed. The perspectives and challenges are also addressed.     

石墨烯基电极材料在超级电容器中的应用

随着能源消耗的日渐增长,寻找低成本、环保、寿命长的储能设备迫在眉睫。在超级电容器领域,石墨烯电极材料以其高比电容、优异倍率性能、良好导电性等优势而受到广泛关注。对石墨烯材料的制备方法、电化学性能及相关机制做了总结,目的是研究不同结构的石墨烯材料对超级电容器性能的影响,并找到性能较为优异的石墨烯基材料。最后分析了石墨烯基电极材料发展中存在的问题,并对其研究前景进行了展望。     

Graphene-based hybrid materials and their applications in energy storage and conversion

Graphene attracts more and more scientists and researchers owing to its superior electronic,thermal,and mechanical properties.For material scientists,graphene is a kind of versatile building blocks,and considerable progress has been made in recent years.Graphene-based hybrid materials have been prepared by incorporating inorganic species and/or cross-linking of organic species through covalent and/or noncovalent interactions.The graphene-based hybrid materials show improved or excellent performance in various fields.In this review,we summarize the synthesis of graphene and graphene-based hybrid materials,and their applications in energy storage and conversion.     

Unique synthesis of graphene-based materials for clean energy and biological sensing applications

Graphene has unique physical properties,and a variety of proof-of-concept devices based on graphene have been demonstated.A prerequisite for the application of graphene is its production in a controlled manner because the number of graphene layers and the defects in these layers significantly influence transport properties.In this paper,we briefly review our recent work on the controlled synthesis of graphene and graphene-based composites,the development of methods to characterize graphene layers,and the use of graphene in clean energy applications and for rapid DNA sequencing.For example,we have used Auger electron spectroscopy to characterize the number and structure of graphene layers,produced single-layer graphene over a whole Ni film substrate,synthesized well-dispersed reduced graphene oxide that was uniformly grafted with unique gold nanodots,and fabricated graphene nanoscrolls.We have also explored applications of graphene in organic solar cells and direct,ultrafast DNA sequencing.Finally,we address the challenges that graphene still face in its synthesis and clean energy and biological sensing applications.     

石墨烯在强化传热领域的研究进展

 石墨烯是一种单原子层厚度的二维平面碳纳米材料,具有超高的载流子迁移率、高热导率等特性。本文综述目前石墨烯在强化传热领域的研究进展,包括石墨烯热导率的测试方法,以及石墨烯在纳米流体、热界面材料、高导热复合高分子材料方面的应用,并对未来石墨烯的研究方向进行展望。     

Graphene-based composite materials

Graphene sheets--one-atom-thick two-dimensional layers of sp2-bonded carbon--are predicted to have a range of unusual properties. Their thermal conductivity and mechanical stiffness may rival the remarkable in-plane values for graphite (approximately 3,000 W m(-1) K(-1) and 1,060 GPa, respectively); their fracture strength should be comparable to that of carbon nanotubes for similar types of defects; and recent studies have shown that individual graphene sheets have extraordinary electronic transport properties. One possible route to harnessing these properties for applications would be to incorporate graphene sheets in a composite material. The manufacturing of such composites requires not only that graphene sheets be produced on a sufficient scale but that they also be incorporated, and homogeneously distributed, into various matrices. Graphite, inexpensive and available in large quantity, unfortunately does not readily exfoliate to yield individual graphene sheets. Here we present a general approach for the preparation of graphene-polymer composites via complete exfoliation of graphite and molecular-level dispersion of individual, chemically modified graphene sheets within polymer hosts. A polystyrene-graphene composite formed by this route exhibits a percolation threshold of approximately 0.1 volume per cent for room-temperature electrical conductivity, the lowest reported value for any carbon-based composite except for those involving carbon nanotubes; at only 1 volume per cent, this composite has a conductivity of approximately 0.1 S m(-1), sufficient for many electrical applications. Our bottom-up chemical approach of tuning the graphene sheet properties provides a path to a broad new class of graphene-based materials and their use in a variety of applications.     

石墨烯/聚合物纳米复合材料研究进展

 石墨烯是由单层碳原子通过共价键结合形成的二维片层状结构,是一种新型碳类纳米材料,具有优异的力学、电学和热学等性能,被认为是一种非常有前景的材料,近年来广泛用于改性各种聚合物。本文回顾了石墨烯/聚合物纳米复合材料的制备方法、性能和应用现状;综述了石墨烯/聚合物纳米复合材料的强度、刚度、韧性、电学和热学等性能的研究进展。主要内容包括石墨烯改性聚合物常见的3种制备方法(溶液共混、熔融共混和原位聚合)及其对石墨烯在聚合物基体中分散性的影响,石墨烯/聚合物纳米复合材料力学性能变化规律与作用机理,石墨烯微观结构等因素对材料热学性能以及导电阈值的影响等;讨论了石墨烯/聚合物纳米复合材料的潜在应用和面临的挑战和机遇,并展望了其低成本产业化的发展前景。     

Immobilized ZnO based nanostructures and their environmental applications

In the research of semiconductor metal oxides, zinc oxide (ZnO) nanomaterials have been committed to design and exploration because of their unique physical and chemical properties. ZnO has many structural characteristics and has considerable practical applications in the field of environmental technology. However, ZnO nanomaterials used for environmental functions are often presented in the form of powders. After use, they need to go through recovery processes such as centrifugation and filtration, which is also easy to cause secondary pollution. The above problems can be avoided by fixing ZnO nanostructures on substrates to form easily movable materials. Here, we present a review of our work and some others on the different synthetic strategies, formation mechanism, modification, performance and diversifications of immobilized ZnO based nanostructures, and highlight their photocatalytic related activities for environmental remediation. Various immobilized ZnO based nanostructures including nanorod arrays, 3D nanostructures, and composite heterostructures have been focused. We hope it may serve as a useful reference for researchers interested in immobilized semiconductor nanostructures and their photocatalysis and other environmental applications.     

Highly Sensitive and Portable Gas Sensing System Based on Reduced Graphene Oxide

Graphene has been widely used in gas-sensing applications due to its large specific surface area and strong adsorption ability. Among different forms of graphene used as gas-sensing materials, reduced graphene oxide is one of the most convenient and economical materials to integrate with Si-based electronics, which is very important to graphene-based gas sensors. In addition, the stacking structure of graphene oxide flakes facilitates absorption and detection of gas molecules. Based on reduced graphene oxide, a highly sensitive and portable gas-sensing system was demonstrated here. Solution-based graphene oxide was cast on a chip like a TF memory card and then reduced thermally. A signal acquisition system was designed to monitor resistance variation as a sign of gas concentration. This miniature graphene-based gas sensor array demonstrates a new path for the use of graphene in gas-detection technologies. And the creation of a sensitive and portable graphene gas sensor also shows great potential in fields such as medicine and environmental science.     

High-conductivity graphene nanocomposite via facile, covalent linkage of gold nanoparticles to graphene oxide

Graphene and its derivative,graphene oxide (GO) have been substantively used as the main framework for dispersing or building nanoarchitectures because of their excellent properties in electronics and catalysis.The requirement to obtain superior graphene-metal hybrid nanomaterials has led us to explore a facile way to design 4-aminobenzenethiol/1-hexanethiolate-protected gold nanoparticles (aAuNPs)-functionalized graphene oxide composite (aAuNPs-GO) in solution.We demonstrate that when aAuNPs with amino groups are exposed to GO,well-dispersed coverage of Au nanoparticles are mainly observed on the edge of GO sheet.In contrast,when 1-hexanethiolate-protected gold nanoparticles (hAuNPs) without amino groups are exposed to GO,hAuNPs simply aggregate on the surface of GO.This indicates that amino groups located on the surface of Au nanoparticles are an essential prerequisite for attachment of nearly monodispersed aAuNPs.The strategy described here for the fabrication of aAuNPs-GO provides a straightforward approach to develop graphene-based nanocomposites with undamaged sheets structure and good solubility and also improve the conductivity of GO sheets evidently.     

Preparation of 3D graphene-based architectures and their applications in supercapacitors

Three dimensional (3D) graphene-based architectures such as 3D graphene-based hydrogels, aerogels, foams, and sponges have attracted huge attention owing to the combination of the structural interconnectivities and the outstanding properties of graphene which offer these interesting structures with low density, high porosity, large surface area, stable mechanical properties, fast mass and electron transport. They have been extensively studied for a wide range of applications including capacitors, batteries, sensors, catalyst, etc. There are several reviews focusing on the 3D graphene-based architectures and their applications. In this work, we only summarise the latest development on the preparation of 3D graphene-based architectures and their applications in supercapacitors, with emphasis on the preparation strategies.     

卤氧化铋光催化去除环境污染物

卤氧化铋基半导体材料具有铋氧层和卤素层交替排布的独特层状结构和易调节的禁带宽度,在直接利用太阳光去除环境污染物方面表现出优异性能和巨大潜力.基于国内外相关研究进展及本课题组近年来的研究成果,该文综述了卤氧化铋材料(氯氧化铋、溴氧化铋和碘氧化铋)光催化去除环境污染物方面的研究成果,主要包括卤氧化铋光催化材料的设计和改性策略,以及上述新材料在重金属离子去除、有机污染物降解和空气净化等领域的研究进展.最后,提出了卤氧化铋光催化材料在环境污染控制领域的研究展望.     

功能化石墨烯在生物医学研究中的应用

石墨烯以其独特的二维结构和优良的电学、光学、热学和机械性能,自2004年来倍受研究人员的高度关注,迅速成为材料、化学、物理和医学领域的热点研究课题.在简要介绍石墨烯基本情况的基础上,重点阐述了石墨烯在生物传感器、靶向给药中的应用.