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1.
光催化技术是解决当今人类社会中环境问题和能源危机两大问题的有效途径,半导体材料在早期的研究中备受青睐。然而,单一半导体光催化剂存在可见光响应程度差、电子空穴对易复合等缺点,光催化技术在降解染料废水的应用中有效率较低,因此研究者对新型复合纳米材料作为光催化剂降解染料废水进行了深入的研究。本文介绍了石墨烯、金属有机骨架、碳量子点三种新型复合纳米材料用于光催化降解染料废水中污染物的研究进展和主要研究结果,按照复合纳米材料设计升级的思路,简述了部分新型复合纳米材料的制备方法,对目标污染物的降解率进行了分析。通过总结新型光催化材料降解水中污染物的性能,对未来发展趋势进行了展望,指出新型复合纳米材料在光催化方向今后的发展趋势和研究重点是有针对性的处理废水,并实现工业化。  相似文献   

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3.
With the advent of carbon nanotechnology, which initiated significant research efforts more than two decades ago, novel materials for energy harvesting and storage have emerged at an amazing pace. Nevertheless, some fundamental applications are still dominated by traditional materials, and it is especially evident in the case of catalysis, and environmental‐related electrochemical reactions, where precious metals such as Pt and Ir are widely used. Several strategies are being explored for achieving competitive and feasible metal‐free carbon nanomaterials, among which doping and defect engineering approaches within nanocarbons are recurrent and promising. Here, the most recent efforts regarding the control of doping and defects in carbon nanostructures for catalysis, and in particular for energy‐related applications, are addressed. Finally, an overview of alternative proposals that can make a difference when enabling carbon nanomaterials as efficient and emerging catalysts is presented.  相似文献   

4.
Tremendous efforts have been devoted to the synthesis and application of two‐dimensional (2D) nanomaterials due to their extraordinary and unique properties in electronics, photonics, catalysis, etc., upon exfoliation from their bulk counterparts. One of the greatest challenges that scientists are confronted with is how to produce large quantities of 2D nanomaterials of high quality in a commercially viable way. This review summarizes the state‐of‐the‐art of the production of 2D nanomaterials using liquid‐based direct exfoliation (LBE), a very promising and highly scalable wet approach for synthesizing high quality 2D nanomaterials in mild conditions. LBE is a collection of methods that directly exfoliates bulk layered materials into thin flakes of 2D nanomaterials in liquid media without any, or with a minimum degree of, chemical reactions, so as to maintain the high crystallinity of 2D nanomaterials. Different synthetic methods are categorized in the following, in which material characteristics including dispersion concentration, flake thickness, flake size and some applications are discussed in detail. At the end, we provide an overview of the advantages and disadvantages of such synthetic methods of LBE and propose future perspectives.  相似文献   

5.
Noble‐metal nanomaterials are attracting increasing research interest due to their promising applications in electrochemical catalysis, for example. Although great efforts have been devoted to the size‐, shape‐, and architecture‐controlled synthesis of noble‐metal nanomaterials, their crystal‐phase‐controlled synthesis is still in its infancy. Here, for the first time, this study reports high‐yield synthesis of Au nanorods (NRs) with alternating 4H/face‐centered cubic (fcc) crystal‐phase heterostructures via a one‐pot wet‐chemical method. The coexistence of 4H and fcc phases is relatively stable, and the 4H/fcc Au NRs can serve as templates for crystal‐phase‐controlled epitaxial growth of other metals. As an example, bimetallic 4H/fcc Au@Pd core–shell NRs are synthesized via the epitaxial growth of Pd on 4H/fcc Au NRs. Significantly, the 4H/fcc Au@Pd NRs show superior mass activity toward the ethanol oxidation reaction, i.e., 6.2 and 4.9 times those of commercial Pd black and Pt/C catalysts, respectively. It is believed that this new synthetic strategy can be used to prepare other novel catalysts for various promising applications.  相似文献   

6.
2D oxide nanomaterials constitute a broad range of materials, with a wide array of current and potential applications, particularly in the fields of energy storage and catalysis for sustainable energy production. Despite the many similarities in structure, composition, and synthetic methods and uses, the current literature on layered oxides is diverse and disconnected. A number of reviews can be found in the literature, but they are mostly focused on one of the particular subclasses of 2D oxides. This review attempts to bridge the knowledge gap between individual layered oxide types by summarizing recent developments in all important 2D oxide systems including supported ultrathin oxide films, layered clays and double hydroxides, layered perovskites, and novel 2D‐zeolite‐based materials. Particular attention is paid to the underlying similarities and differences between the various materials, and the subsequent challenges faced by each research community. The potential of layered oxides toward future applications is critically evaluated, especially in the areas of electrocatalysis and photocatalysis, biomass conversion, and fine chemical synthesis. Attention is also paid to corresponding novel 3D materials that can be obtained via sophisticated engineering of 2D oxides.  相似文献   

7.
Carbon atoms in the graphitic carbon skeleton can be replaced by heteroatoms with different electronegative from that of the carbon atom (i.e., heteroatom doping) to modulate the charge distribution over the carbon network. The charge modulation can be achieved via direct charge transfer with an electron acceptor/donor (i.e., charge transfer doping) or through introduction of defects (i.e., defective doping). Various doping strategies, including heteroatom doping, charge‐transfer doping, and defective doping, have now been devised for modulating the charge distribution of numerous graphite carbon materials to impart new properties to carbon materials. Consequently, carbon nanomaterials with defined doping have recently become prominent members in the carbon family, promising for a variety of applications, including catalysis, energy conversion and storage, environmental remediation, and important chemical production and industrial processes. The purpose of this review is to present an overview on the doping of carbon materials for metal‐free electrocatalysis, especially the development of doping strategies and doping‐induced structure and property changes for potential catalytic applications. Current challenges and future perspectives in the doped carbon‐based metal‐free catalyst field are also discussed.  相似文献   

8.
荧光碳点的制备和性质及其应用研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
荧光碳点是继碳纳米管、纳米金刚石和石墨烯之后,最受关注的碳纳米材料之一。与传统半导体量子点相比,碳点具有优异的荧光性能、小尺寸特性、良好的生物相容性、低毒性以及表面易于化学修饰等特点,在环境检测、生物成像、药物载体、光催化及电催化技术等领域具有很好的潜在应用价值。总结了碳点合成方法、结构与性能及应用面进展,剖析了目前制约碳点应用发展的瓶颈问题,并展望了其未来的研究发展重点方向。   相似文献   

9.
The emergence of metal‐organic frameworks (MOFs) as a new class of crystalline porous materials is attracting considerable attention in many fields such as catalysis, energy storage and conversion, sensors, and environmental remediation due to their controllable composition, structure and pore size. MOFs are versatile precursors for the preparation of various forms of nanomaterials as well as new multifunctional nanocomposites/hybrids, which exhibit superior functional properties compared to the individual components assembling the composites. This review provides an overview of recent developments achieved in the fabrication of porous MOF‐derived nanostructures including carbons, metal oxides, metal chalcogenides (metal sulfides and selenides), metal carbides, metal phosphides and their composites. Finally, the challenges and future trends and prospects associated with the development of MOF‐derived nanomaterials are also examined.  相似文献   

10.
Covalent organic frameworks (COFs), connecting different organic units into one system through covalent bonds, are crystalline organic porous materials with 2D or 3D networks. Compared with conventional porous materials such as inorganic zeolite, active carbon, and metal‐organic frameworks, COFs are a new type of porous materials with well‐designed pore structure, high surface area, outstanding stability, and easy functionalization at the molecular level, which have attracted extensive attention in various fields, such as energy storage, gas separation, sensing, photoluminescence, proton conduction, magnetic properties, drug delivery, and heterogeneous catalysis. Herein, the recent advances in metal‐free COFs as a versatile platform for heterogeneous catalysis in a wide range of chemical reactions are presented and the synthetic strategy and promising catalytic applications of COF‐based catalysts (including photocatalysis) are summarized. According to the types of catalytic reactions, this review is divided into the following five parts for discussion: achiral organic catalysis, chiral organic conversion, photocatalytic organic reactions, photocatalytic energy conversion (including water splitting and the reduction of carbon dioxide), and photocatalytic pollutant degradation. Furthermore, the remaining challenges and prospects of COFs as heterogeneous catalysts are also presented.  相似文献   

11.
One dimensional (1D) silver‐based nanomaterials have a great potential in various fields because of their high specific surface area, high electric conductivity, optoelectronic properties, mechanical flexibility and high electro‐catalytic efficiency. In this Review, the preparations of 1D silver‐based nanomaterials is classified by structure composed of simple silver nanowires/rods/belts/tubes, core‐shells, and hybrids. The latest applications based on 1D silver nanomaterials and their composite materials are summarized systematically including electrochemical capacitors, lithium‐ion/lithium‐oxygen batteries, electrochemical sensors and electrochemical catalysis. The preparation process, tailored material properties and electrochemical applications are discussed.  相似文献   

12.
Carbon nanomaterials have advanced rapidly over the last two decades and are among the most promising materials that have already changed and will keep on changing human life. Development of synthetic methodologies for these materials, therefore, has been one of the most important subjects of carbon nanoscience and nanotechnology, and forms the basis for investigating the physicochemical properties and applications of carbon nanomaterials. In this Research News article, several synthetic strategies, including solvothermal reduction, solvothermal pyrolysis, hydrothermal carbonization, and soft‐chemical exfoliation are specifically discussed and highlighted, which have been developed for the synthesis of novel carbon nanomaterials over the last decade.  相似文献   

13.
Surface‐enhanced Raman spectroscopy is a powerful and sensitive analytical tool that has found application in chemical and biomolecule analysis and environmental monitoring. Since its discovery in the early 1970s, a variety of materials ranging from noble metals to nanostructured materials have been employed as surface enhanced Raman scattering (SERS) substrates. In recent years, 2D inorganic materials have found wide use in the development of SERS‐based chemical sensors owing to their unique thickness dependent physico‐chemical properties with enhanced chemical‐based charge‐transfer processes. Here, recent advances in the application of various 2D inorganic nanomaterials, including graphene, boron nitride, semiconducting metal oxides, and transition metal chalcogenides, in chemical detection via SERS are presented. The background of the SERS concept, including its basic theory and sensing mechanism, along with the salient features of different nanomaterials used as substrates in SERS, extending from monometallic nanoparticles to nanometal oxides, is comprehensively discussed. The importance of 2D inorganic nanomaterials in SERS enhancement, along with their application toward chemical detection, is explained in detail with suitable examples and illustrations. In conclusion, some guidelines are presented for the development of this promising field in the future.  相似文献   

14.
碳纳米管作为一种新型准一维功能材料已成为物理、化学和材料科学等领域的研究热点.由于缺乏微观上的加工处理方法,碳纳米管的应用受到一定程度的限制.磁性纳米材料由于其特殊的物理化学性质在存储器、传感器和环境保护等方面得到了广泛的应用.将磁性纳米粒子与碳纳米管复合不但可以使碳纳米管功能化改性,而且还可通过复合纳米管对磁场的响应对其进行加工处理.综述了碳纳米管与磁性粒子复合的制备技术,并展望了磁性复合碳纳米管的应用及其前景.  相似文献   

15.
Graphdiyne is a new member of the family of carbon‐based nanomaterials that possess two types of carbon atoms, sp‐ and sp2‐hybridized carbon atoms. As a novel 2D carbon‐based nanomaterial with unique planar structure, such as uniformly distributed nanopores and large conjugated structure, graphdiyne has shown many fascinating properties in mechanics, electronics, and optics since it was first experimentally synthesized in 2010. Up to now, graphdiyne and its derivatives have been reported to be successfully applied in many areas, such as catalysis, energy, environment, and biomedicine, due to these excellent properties. Herein, the current research progress of graphdiyne‐based materials in biomedical fields is summarized, including biosensing, biological protection, cancer therapy, tissue engineering, etc. The advantages of graphdiyne and its derivatives are presented and compared with other carbon‐based materials. Considering the potential biomedical and clinical applications of graphdiyne‐based materials, the toxicity and biocompatibility are also discussed based on current studies. Finally, future perspectives and possible biomedical applications of graphdiyne‐based materials are also discussed.  相似文献   

16.
Carbon nanotubes (CNTs) as well‐known nanomaterials are extensively studied and widely applied in various fields. Nitric acid (HNO3) is often used to treat CNTs for purification purposes and preparing oxidized CNTs for various applications. However, too little attention is paid to investigating the effect of HNO3 treatment on the optical properties of CNTs. In this work, it is observed for the first time that HNO3‐oxidized multiwalled carbon nanotubes (ox‐MWCNTs) have strong electrochemiluminescence (ECL) activity, which enables ox‐MWCNTs to become new and good ECL carbon nanomaterials after carbon quantum dots (CQDs) and graphene quantum dots (GQDs). Various characterization technologies, such as transmission electron microscope (TEM), X‐ray photoelectron spectroscopy (XPS), and Raman spectroscopy, are used to reveal the relationship between ECL activity and surface states. The ECL behaviors of ox‐MWCNTs are investigated in detail and a possible ECL mechanism is proposed. Finally, the new ECL nanomaterials of ox‐MWCNTs are envisioned to have promising applications in sensitive ECL sensing and in the study of CNT‐based catalysts.  相似文献   

17.
Half a century after its initial emergence, lanthanide photonics is facing a profound remodeling induced by the upsurge of nanomaterials. Lanthanide‐doped nanomaterials hold promise for bioapplications and photonic devices because they ally the unmatched advantages of lanthanide photophysical properties with those arising from large surface‐to‐volume ratios and quantum confinement that are typical of nanoobjects. Cutting‐edge technologies and devices have recently arisen from this association and are in turn promoting nanophotonic materials as essential tools for a deeper understanding of biological mechanisms and related medical diagnosis and therapy, and as crucial building blocks for next‐generation photonic devices. Here, the recent progress in the development of nanomaterials, nanotechnologies, and nanodevices for clinical uses and commercial exploitation is reviewed. The candidate nanomaterials with mature synthesis protocols and compelling optical uniqueness are surveyed. The specific fields that are directly driven by lanthanide doped nanomaterials are emphasized, spanning from in vivo imaging and theranostics, micro‐/nanoscopic techniques, point‐of‐care medical testing, forensic fingerprints detection, to micro‐LED devices.  相似文献   

18.
2D porous carbon nanomaterials have attracted tremendous attention in different disciplines especially for electrochemical catalysis. The significant advantage of such 2D materials is that nearly all their surfaces are exposed to the electrolyte and can take part in the electrochemical reaction. Here, a versatile active‐salt‐templating strategy to efficiently synthesize 2D porous carbon nanosheets from layered organic–inorganic hybrids is presented. The resulting heteroatom‐doped carbon nanosheets (NFe/CNs) exhibit exceptional performance for the oxygen‐reduction reaction and in Zn–air battery electrodes. The activity of the best catalyst within a series of NFe/CNs exceeds the performance of conventional carbon‐supported Pt catalysts in terms of onset potential (0.930 vs 0.915 V of Pt/C), half‐wave potential (0.859 vs 0.816 V of Pt/C), long‐time stability, and methanol tolerance. Also, when applied as a cathode catalyst in a zinc–air battery the NFe/CNs presented here outperform commercial Pt/C catalysts.  相似文献   

19.
As a new class of luminescent nanomaterials, carbon dots (CDs) have aroused significant interest because of their fascinating photoluminescence properties and potential applications in biological, optoelectronic, and energy‐related fields. Strikingly, embedding CDs in host matrices endow them with intriguing luminescent properties, in particular, room temperature phosphorescence and thermally activated delayed fluorescence, due to the confinement effect of the host matrix and the H‐bonding interactions between CDs and the matrix. Here, the state‐of‐the‐art strategies for introducing CDs in various host matrices are summarized, such as nanoporous materials, polyvinyl alcohol, polyurethane, potash alum, layered double hydroxides, amorphous silica, etc. The resultant luminescent properties of the composites and their emission mechanisms are discussed. Their applications in bioimaging, drug delivery/release, sensing, and anticounterfeiting are also presented. Finally, current problems and challenges of CDs‐based composites are noted for future development of such luminescent materials.  相似文献   

20.
Biomolecular nanostructures in nature are drawing increasing interests in the field of materials sciences. As a typical group of them, virus‐based nanoparticles (VNPs), which are nanocages or nanorods assembled from capsid proteins of viruses, have been widely exploited as templates to guide the fabrication of complex nanoarchitectures (NAs), because of their appropriate sizes (ca. 20–200 nm), homogeneity, addressable functionalization, facile modification via chemical and genetic routes, and convenient preparation. Foreign materials can be positioned in the inner cavity or on the outer surface of VNPs, through either direct synthesis or assembling preformed nanomaterials. Simultaneous use of the inner and outer space of VNPs facilitates integration of multiple functionalities in a single NA. This review briefly summarizes the strategies for fabrication of NAs templated by VNPs and wide applications of these NAs in fields of catalysis, energy, biomedicine, and nanophotonics, etc.  相似文献   

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