共查询到19条相似文献,搜索用时 71 毫秒
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以钨酸钠和半胱氨酸为原料, 采用水热法一步合成了具有超小粒径(约2 nm)的二硫化钨荧光量子点(WS2 QDs). 利用透射电子显微镜(TEM)、 荧光光谱、 X射线光电子能谱(XPS)、 红外光谱(FTIR)和X射线衍射光谱(XRD)对其进行了表征, 并考察了其稳定性和细胞毒性. 结果表明, 制备的WS2 QDs具有水溶性好、 稳定性高和细胞毒性低的优点. 将此WS2 QDs用于人乳腺癌细胞(MCF-7)的成像, 并通过溶酶体荧光探针进行共定位, 发现此WS2 QDs可能借助溶酶体进入细胞内. 相似文献
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以六氯化钨、硫代乙酰胺、氧化石墨烯为原料,采用一步水热法合成了二维的二硫化钨/石墨烯(WS2/RGO)复合材料。水热合成的WS2/RGO具有薄层的二维结构,且由于石墨烯的存在,WS2以较少的层数形成薄片状生长在石墨烯的表面。尝试将这种非Pt类材料用于电催化氧化原反应,测试结果表明,WS2在碱性条件下氧还原活性非常低,但是复合RGO形成WS2/RGO复合材料后,电催化氧化原性能有了极大的提高,其起始电位为-0.17 V(vs SCE),转移电子数为3.7,极限电流密度为2.5 mA·cm-2,同时其具有较好的抗甲醇性能和循环稳定性。这是因为WS2/RGO复合材料的二维结构具有更高的电子传输速率,同时硫化钨和石墨烯可以发挥协同催化作用。这种新型的二硫化钨/石墨烯(WS2/RGO)复合材料作为非贵金属催化剂表现出良好的氧还原性能,在燃料电池上具有较好的应用前景。 相似文献
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以六氯化钨、硫代乙酰胺、氧化石墨烯为原料,采用一步水热法合成了二维的二硫化钨/石墨烯(WS_2/RGO)复合材料。水热合成的WS_2/RGO具有薄层的二维结构,且由于石墨烯的存在,WS_2以较少的层数形成薄片状生长在石墨烯的表面。尝试将这种非Pt类材料用于电催化氧化原反应,测试结果表明,WS_2在碱性条件下氧还原活性非常低,但是复合RGO形成WS_2/RGO复合材料后,电催化氧化原性能有了极大的提高,其起始电位为-0.17 V(vs SCE),转移电子数为3.7,极限电流密度为2.5 m A·cm-2,同时其具有较好的抗甲醇性能和循环稳定性。这是因为WS_2/RGO复合材料的二维结构具有更高的电子传输速率,同时硫化钨和石墨烯可以发挥协同催化作用。这种新型的二硫化钨/石墨烯(WS_2/RGO)复合材料作为非贵金属催化剂表现出良好的氧还原性能,在燃料电池上具有较好的应用前景。 相似文献
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化学剥离的硫化钨二维层状材料在经过紫外臭氧处理后用作有机太阳能电池的空穴传输层, 可以显著提高电池器件的光电转化效率至8.37%; 作为空穴传输层, 硫化钨二维层状材料可以与经典的空穴传输材料PEDOT:PSS相媲美. 利用X射线光电子能谱(XPS)、拉曼光谱(Raman)、原子力显微镜(AFM)对硫化钨的结构和形貌进行分析. 结果表明, 紫外臭氧处理过后, 氧原子能填充硫化钨因锂插层剥离而产生的硫空位, 减少它的缺陷, 并且使其部分被氧化, 从而改善硫化钨的电学性能. 相似文献
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新型中介结构层状硫化钨的合成与表征 总被引:3,自引:0,他引:3
利用钨酸钠与表面活性剂十六烷基三甲基溴化铵(CTAB)及硫代乙酰胺在水热条件下合成了一种中介结构层状硫化钨WS-L.通过化学及元素分析、红外光谱、光电子能谱、粉末X射线衍射、透射电镜、扫描电镜以及热重分析等方法进行表征.WS-L的化学式为WS3.5·[C16H33N(CH3)3]2,其中硫化钨所带负电荷被嵌插在层间的表面活性剂阳离子所平衡. 相似文献
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基于各种电化学过程的能源转化技术是未来可持续能源利用和发展的关键, 而催化剂在其中扮演着非常重要的角色. 二维金属纳米材料因其独特的物理化学性质在许多电催化反应中都展现出巨大的应用潜力, 也因此受到了广泛关注. 本文介绍了二维金属纳米材料的常见合成方法与策略, 并综合评述了近年来该类材料在电催化应用领域中的研究进展, 重点探讨了材料的组分和微观结构等因素对其性能的影响机理, 最后对二维金属纳米材料目前所面临的挑战以及未来的研究方向进行了总结与展望. 相似文献
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The crystal structures of the 2H- and 3R-forms of WS2 have been refined from single-crystal data. The results are summarized and the interatomic distances are compared with those in related compounds. 相似文献
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《Electrochemistry communications》2007,9(1):119-122
A novel method (a rheological phase reaction) was used to synthesize WS2 nanoflakes by adding oxalic acid as a reducing reagent. High resolution electron microscopy observations revealed that the as-prepared WS2 nanoflakes had started to curve and that WS2 nanotubes were partly formed. The lithium intercalation/deintercalation behavior of as-prepared WS2 electrode was also investigated. It was found that the WS2 nanoflake electrode exhibited higher specific capacity with very good cycling stability compared to WS2 nanotube or nanoparticle electrodes. The reasons for the improved electrochemical performance of the nanoflake electrodes are also discussed. 相似文献
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S. E. Alexandrov K. D. Filatov A. B. Speshilova K. S. Tyurikov V. D. Andreeva D. A. Kirilenko 《Russian Journal of Applied Chemistry》2016,89(12):1948-1954
Solutions of ammonium thiotungstate in dimethylformamide were used to synthesize spherical tungsten disulfide particles with average radius of 500–100 nm by the method of aerosol-assisted chemical vapor deposition. Nanoparticles with composition close to stoichiometric tungsten disulfide are formed at pyrolysis temperatures not lower than 800°C. It was found that the average particle radius linearly decreases as the reagent concentration in solution becomes lower, and the nebulizer power has no effect within the range under study on the size characteristics and structure of the particles obtained. It was demonstrated that the particles have a layered structure that is formed in all probability by S–W–S packets, which must provide high antifriction properties of the material in its use as a high-temperature solid lubricant. The results obtained indicate that the size of tungsten disulfide particles can be controlled in a wide range in the course of the aerosol-assisted chemical vapor deposition. This may be of interest for developing a technology for creating high-temperature wear-resistant antifriction coatings. 相似文献
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随着分析化学所面临的样品性质的复杂程度越来越高,被检测物质的浓度要求越来越低,在色谱及质谱分析前进行准确、高效的样品前处理过程就显得尤为重要。磁性固相萃取法由于其合成方法简单、易于分离、萃取效率高等优点,被认为是一种高效的样品预处理方法。Fe3O4磁性纳米材料由于分离速度快,分散性、生物相容性好等特点,近年来被广泛用于分离分析等各个领域。为了提高Fe3O4磁性纳米材料的物理和化学的稳定性,使其具备更高效的吸附分离能力,需要对其进行功能化的修饰。本文综述了近年来由碳基纳米材料、分子印迹聚合物、离子液体、硼酸亲和配体、金属有机骨架、共价有机骨架、量子点、金属氧化物等功能化磁性纳米材料的制备及其在生物、环境污染物、食品样品等样品前处理中的应用,并对这一领域发展进行了展望。 相似文献
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抗菌涂料广泛应用于医疗保健、食品保鲜和医院消毒等多个行业领域。石墨烯是目前最受欢迎的纳米材料之一,在抗菌方面细菌表现出低耐药性,同时对哺乳动物细胞有较小的细胞毒性。石墨烯从物理和化学两个层面协同发挥抑菌效果,物理方面其尖锐边缘与细菌细胞膜的直接接触从而对脂质分子进行破坏性提取,而化学方面通过氧化应激所产生的活性氧以及电荷转移破坏细菌细胞膜。此外,石墨烯用于作为分散和稳定各种纳米材料的载体,且得益于材料之间的协同作用,其复合材料具有较高的抗菌效率和良好的生物相容性,目前已在抗菌包装、伤口敷料和器械表面清洁等方面投入使用。本文首先概述了石墨烯的结构、安全性以及抗菌机理,对石墨烯复合涂层所取得的重要成果进行简要总结,最后综述了石墨烯材料在支架表面改性中的研究进展,展望了石墨烯抗菌涂层的未来发展趋势。 相似文献
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Yanxin Lv Song Jin Yu Wang Zhiqiang Lun Chunhui Xia 《Journal of the Iranian Chemical Society》2016,13(10):1767-1776
Due to the critical role of glucose level in the diagnosis and treatment of diabetes, as well as the increasing number of diabetics, there is an overwhelming demand for developing glucose sensors. It is well acknowledged that these sensors, especially those based on glucose oxidase, have played an important role in blood glucose detection. Inspired by the attractive properties, nanomaterials, especially nanostructured carbon and metal/metal oxides, have been extensively explored to develop enzymatic glucose sensors with high sensitivity, fast response time, and satisfied stability. In this review, a brief history of glucose biosensors is firstly presented. Furthermore, we discuss the currently available fabrication possesses in the field of enzymatic glucose biosensors based on nanomaterials, focusing on the carbon-based, metal-based, and metal oxides-based nanocomposites. What is more, we discuss the challenges and attempt to give an outlook on the possible further developments. 相似文献
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《Solid State Sciences》2000,2(6):663-672
MS2 (M=Mo, W) hollow onion-like nanoparticles were the first inorganic fullerene-like (IF) materials, found in 1992. Understanding of the IF-MS2 growth mechanism in 1996 enabled us to build a rather simple reactor, which produced about 0.4 g per batch, of an almost pure IF-WS2 powder. Soon after, it was found that the new powder showed better tribological properties compared with the regular MS2 (M=Mo, W) powder, which is a well-known solid lubricant. The present work shows a new synthetic approach, which allows for a scale-up of IF-WS2 production by more than two orders of magnitude. The falling-bed and, especially, fluidized-bed methods, which are presented here, pave the way for an almost ideal growth condition of the IF synthesis from an oxide precursor. As a result, the presently produced IF has a more uniform (spherical) shape and can grow to a larger size (up to 0.5 μm). It is expected that the relatively spherical IF-WS2 nanoparticles, which are produced by the falling (fluidized) bed reactor, will exhibit superior tribological properties, than reported before. 相似文献
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Hui Wang Junlei Yang Penghui Cao Ning Guo Yuhao Li Yuefeng Zhao Shuang Zhou Ruizhuo Ouyang Yuqing Miao 《中国化学快报》2021,31(12):3015-3026
Multifunctional bismuth sulfide (Bi2S3) nanomaterials exhibit significant potential as nanomedicines for the diagnosis and treatment of cancer. These nanomaterials act as excellent photothermal agents and radiation sensitizers for the treatment of tumors, and they can also act as contrast agents for computed tomography (CT) imaging, photoacoustic imaging (PA), and other forms of imaging to provide real-time tumor monitoring and testing guidance. Compared with other nanomaterials, Bi2S3 nanomaterials can readily adapt to different applications by virtue of the fact that they can be easily functionalized. However, these nanomaterials have some limitations that cannot be ignored and need to be addressed, such as poor biocompatibility, toxicity, and low chemical stability. It is widely believed that appropriate functionalization of Bi2S3 nanomaterials could remedy such defects and significantly improve performance. This review summarizes the ways in which Bi2S3 nanomaterials can be functionalized and discusses their applications in cancer theranostics over the last few years, focusing particularly on imaging and therapy. We also discuss issues relating to how Bi2S3 nanomaterials can be analyzed, including how we might be able to use these systems to inhibit and treat tumors and how current limitations might be overcome to improve treatment efficacy. Finally, we hope to provide inspiration and guidance as to how we might create a more optimized multifunctional nano-system for the diagnosis and treatment of tumors. 相似文献