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  1613-6829

  1613-6810

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Cơ quản chủ quản:  Wiley-VCH Verlag , WILEY-V C H VERLAG GMBH

Lĩnh vực:
Medicine (miscellaneous)BiomaterialsNanoscience and NanotechnologyChemistry (miscellaneous)Materials Science (miscellaneous)Engineering (miscellaneous)Biotechnology

Các bài báo tiêu biểu

Cytotoxicity of Nanoparticles
Tập 4 Số 1 - Trang 26-49 - 2008
Nastassja A. Lewinski, Vicki L. Colvin, Rebekah Drezek
AbstractHuman exposure to nanoparticles is inevitable as nanoparticles become more widely used and, as a result, nanotoxicology research is now gaining attention. However, while the number of nanoparticle types and applications continues to increase, studies to characterize their effects after exposure and to address their potential toxicity are few in comparison. In the medical field in particular, nanoparticles are being utilized in diagnostic and therapeutic tools to better understand, detect, and treat human diseases. Exposure to nanoparticles for medical purposes involves intentional contact or administration; therefore, understanding the properties of nanoparticles and their effect on the body is crucial before clinical use can occur. This Review presents a summary of the in vitro cytotoxicity data currently available on three classes of nanoparticles. With each of these nanoparticles, different data has been published about their cytotoxicity due to varying experimental conditions as well as differing nanoparticle physiochemical properties. For nanoparticles to move into the clinical arena, it is important that nanotoxicology research uncovers and understands how these multiple factors influence the toxicity of nanoparticles so that their undesirable properties can be avoided.
Graphene Oxide, Highly Reduced Graphene Oxide, and Graphene: Versatile Building Blocks for Carbon‐Based Materials
Tập 6 Số 6 - Trang 711-723 - 2010
Owen C. Compton, SonBinh T. Nguyen
AbstractIsolated graphene, a nanometer‐thick two‐dimensional analog of fullerenes and carbon nanotubes, has recently sparked great excitement in the scientific community given its excellent mechanical and electronic properties. Particularly attractive is the availability of bulk quantities of graphene as both colloidal dispersions and powders, which enables the facile fabrication of many carbon‐based materials. The fact that such large amounts of graphene are most easily produced via the reduction of graphene oxide—oxygenated graphene sheets covered with epoxy, hydroxyl, and carboxyl groups—offers tremendous opportunities for access to functionalized graphene‐based materials. Both graphene oxide and graphene can be processed into a wide variety of novel materials with distinctly different morphological features, where the carbonaceous nanosheets can serve as either the sole component, as in papers and thin films, or as fillers in polymer and/or inorganic nanocomposites. This Review summarizes techniques for preparing such advanced materials via stable graphene oxide, highly reduced graphene oxide, and graphene dispersions in aqueous and organic media. The excellent mechanical and electronic properties of the resulting materials are highlighted with a forward outlook on their applications.
Graphene‐Based Materials: Synthesis, Characterization, Properties, and Applications
Tập 7 Số 14 - Trang 1876-1902 - 2011
Xiao Huang, Zongyou Yin, Shixin Wu, Xiaoying Qi, Qiyuan He, Qichun Zhang, Qingyu Yan, Freddy Boey, Hua Zhang
AbstractGraphene, a two‐dimensional, single‐layer sheet of sp2 hybridized carbon atoms, has attracted tremendous attention and research interest, owing to its exceptional physical properties, such as high electronic conductivity, good thermal stability, and excellent mechanical strength. Other forms of graphene‐related materials, including graphene oxide, reduced graphene oxide, and exfoliated graphite, have been reliably produced in large scale. The promising properties together with the ease of processibility and functionalization make graphene‐based materials ideal candidates for incorporation into a variety of functional materials. Importantly, graphene and its derivatives have been explored in a wide range of applications, such as electronic and photonic devices, clean energy, and sensors. In this review, after a general introduction to graphene and its derivatives, the synthesis, characterization, properties, and applications of graphene‐based materials are discussed.
Optical Properties of ZnO Nanostructures
Tập 2 Số 8-9 - Trang 944-961 - 2006
Aleksandra B. Djurišić, Yu Hang Leung
AbstractWe present a review of current research on the optical properties of ZnO nanostructures. We provide a brief introduction to different fabrication methods for various ZnO nanostructures and some general guidelines on how fabrication parameters (temperature, vapor‐phase versus solution‐phase deposition, etc.) affect their properties. A detailed discussion of photoluminescence, both in the UV region and in the visible spectral range, is provided. In addition, different gain (excitonic versus electron hole plasma) and feedback (random lasing versus individual nanostructures functioning as Fabry–Perot resonators) mechanisms for achieving stimulated emission are described. The factors affecting the achievement of stimulated emission are discussed, and the results of time‐resolved studies of stimulated emission are summarized. Then, results of nonlinear optical studies, such as second‐harmonic generation, are presented. Optical properties of doped ZnO nanostructures are also discussed, along with a concluding outlook for research into the optical properties of ZnO.
Large‐Area Vapor‐Phase Growth and Characterization of MoS<sub>2</sub> Atomic Layers on a SiO<sub>2</sub> Substrate
Tập 8 Số 7 - Trang 966-971 - 2012
Yongjie Zhan, Zheng Liu, Sina Najmaei, Pulickel M. Ajayan, Jun Lou
Fabrication of Single‐ and Multilayer MoS<sub>2</sub> Film‐Based Field‐Effect Transistors for Sensing NO at Room Temperature
Tập 8 Số 1 - Trang 63-67 - 2012
Hai Li, Zongyou Yin, Qiyuan He, Hong Li, Xiao Huang, Gang Lü, Derrick Wen Hui Fam, Alfred Iing Yoong Tok, Qing Zhang, Hua Zhang
Carbon Nanomaterials for Advanced Energy Conversion and Storage
Tập 8 Số 8 - Trang 1130-1166 - 2012
Liming Dai, Dong Wook Chang, Jong‐Beom Baek, Wen Lu
AbstractIt is estimated that the world will need to double its energy supply by 2050. Nanotechnology has opened up new frontiers in materials science and engineering to meet this challenge by creating new materials, particularly carbon nanomaterials, for efficient energy conversion and storage. Comparing to conventional energy materials, carbon nanomaterials possess unique size‐/surface‐dependent (e.g., morphological, electrical, optical, and mechanical) properties useful for enhancing the energy‐conversion and storage performances. During the past 25 years or so, therefore, considerable efforts have been made to utilize the unique properties of carbon nanomaterials, including fullerenes, carbon nanotubes, and graphene, as energy materials, and tremendous progress has been achieved in developing high‐performance energy conversion (e.g., solar cells and fuel cells) and storage (e.g., supercapacitors and batteries) devices. This article reviews progress in the research and development of carbon nanomaterials during the past twenty years or so for advanced energy conversion and storage, along with some discussions on challenges and perspectives in this exciting field.
Perovskite Solar Cells: From Materials to Devices
Tập 11 Số 1 - Trang 10-25 - 2015
Hyun Suk Jung, Nam‐Gyu Park
Perovskite solar cells based on organometal halide light absorbers have been considered a promising photovoltaic technology due to their superb power conversion efficiency (PCE) along with very low material costs. Since the first report on a long‐term durable solid‐state perovskite solar cell with a PCE of 9.7% in 2012, a PCE as high as 19.3% was demonstrated in 2014, and a certified PCE of 17.9% was shown in 2014. Such a high photovoltaic performance is attributed to optically high absorption characteristics and balanced charge transport properties with long diffusion lengths. Nevertheless, there are lots of puzzles to unravel the basis for such high photovoltaic performances. The working principle of perovskite solar cells has not been well established by far, which is the most important thing for understanding perovksite solar cells. In this review, basic fundamentals of perovskite materials including opto‐electronic and dielectric properties are described to give a better understanding and insight into high‐performing perovskite solar cells. In addition, various fabrication techniques and device structures are described toward the further improvement of perovskite solar cells.
Fluorographene: A Two‐Dimensional Counterpart of Teflon
Tập 6 Số 24 - Trang 2877-2884 - 2010
Rahul R. Nair, Wencai Ren, R. Jalil, Ibtsam Riaz, Vasyl G. Kravets, L. Britnell, Peter Blake, Fredrik Schedin, Alexander S. Mayorov, Shengjun Yuan, M. I. Katsnelson, Hui‐Ming Cheng, Włodek Strupiński, Lyubov G. Bulusheva, А. В. Окотруб, I. V. Grigorieva, A. N. Grigorenko, Kostya S. Novoselov, A. K. Geǐm
AbstractA stoichiometric derivative of graphene with a fluorine atom attached to each carbon is reported. Raman, optical, structural, micromechanical, and transport studies show that the material is qualitatively different from the known graphene‐based nonstoichiometric derivatives. Fluorographene is a high‐quality insulator (resistivity >1012 Ω) with an optical gap of 3 eV. It inherits the mechanical strength of graphene, exhibiting a Young’s modulus of 100 N m−1 and sustaining strains of 15%. Fluorographene is inert and stable up to 400 °C even in air, similar to Teflon.
Hierarchical Porous O‐Doped g‐C<sub>3</sub>N<sub>4</sub> with Enhanced Photocatalytic CO<sub>2</sub> Reduction Activity
Tập 13 Số 15 - 2017
Junwei Fu, Bicheng Zhu, Chuanjia Jiang, Bei Cheng, Wei You
Artificial photosynthesis of hydrocarbon fuels by utilizing solar energy and CO2 is considered as a potential route for solving ever‐increasing energy crisis and greenhouse effect. Herein, hierarchical porous O‐doped graphitic carbon nitride (g‐C3N4) nanotubes (OCN‐Tube) are prepared via successive thermal oxidation exfoliation and curling‐condensation of bulk g‐C3N4. The as‐prepared OCN‐Tube exhibits hierarchically porous structures, which consist of interconnected multiwalled nanotubes with uniform diameters of 20–30 nm. The hierarchical OCN‐Tube shows excellent photocatalytic CO2 reduction performance under visible light, with methanol evolution rate of 0.88 µmol g−1 h−1, which is five times higher than bulk g‐C3N4 (0.17 µmol g−1 h−1). The enhanced photocatalytic activity of OCN‐Tube is ascribed to the hierarchical nanotube structure and O‐doping effect. The hierarchical nanotube structure endows OCN‐Tube with higher specific surface area, greater light utilization efficiency, and improved molecular diffusion kinetics, due to the more exposed active edges and multiple light reflection/scattering channels. The O‐doping optimizes the band structure of g‐C3N4, resulting in narrower bandgap, greater CO2 affinity, and uptake capacity as well as higher separation efficiency of photogenerated charge carriers. This work provides a novel strategy to design hierarchical g‐C3N4 nanostructures, which can be used as promising photocatalyst for solar energy conversion.