共查询到18条相似文献,搜索用时 859 毫秒
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自从1992年首次报道介孔氧化硅分子筛M41S系列以来, 人们采用各种商业化表面活性剂为模板, 合成了多种骨架组成、丰富的有序介观结构、不同孔径尺寸的介孔材料, 并将其应用在能源、环境、催化等诸多领域。然而, 由于常规商业化模板剂的分子量大小有限, 合成的介孔材料具有较小的孔径(< 8.0 nm), 从而极大地限制了其面对大尺寸客体分子的相关应用。此外, 利用常规模板剂难以合成出具有晶化墙壁的介孔金属氧化物材料。近年来, 大分子量两亲性嵌段共聚物相继被报道用来合成新型介孔材料, 本文将综述基于这种嵌段共聚物为模板剂合成各种具有大孔径和晶化墙壁介孔材料的研究进展。 相似文献
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Highly ordered mesoporous silica and aluminosilicate materials with extremely high hydrothermal stability have been synthesized successfully at a high hydrothermal treatment temperature of 200 °C by using inexpensive sodium silicate and sodium aluminate as the silica source and alumina source, respectively. The resultant mesoporous materials possess a hexagonal mesostructure and extraordinary stability towards the steam treatment at 800 °C for 2 h. In addition, the direct incorporation of Al into the mesoporous framework can further enhance the hydrothermal stability of ordered mesoporous materials. Our contribution provides a commercially important approach to synthesize ordered mesoporous materials with highly hydrothermal stability, which may find potential applications for the catalytic cracking in the petroleum industry. 相似文献
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采用微湿含浸法制备了一系列具有不同比表面积和孔径分布的超级电容器有序中孔炭材料。采用液氮吸附脱附等温线、小角XRD以及TEM表征了有序中孔炭的孔结构,在1MEt4NBF4|PC电解液中测试了其电化学性能。结果表明,所制得的有序中孔炭的BET比表面积随糠醇加入量的增加先增加后减小,糠醇加入量少制得具有CMK-5结构的有序中孔炭,加入量多制得的CMK-3结构。电化学性能测试结果表明,在1mA·cm-2的充放电电流密度下各有序中孔炭材料比电容的大小顺序与其BET比表面积的大小顺序基本一致,具有CMK-3结构的有序中孔炭的倍率性能最好,并且也好于无序中孔炭的。 相似文献
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A new and efficient method for the preparation of MCM-41 type ordered mesoporous phases using phosphate as promoter under
reflux conditions is reported. The various mesoporous materials studied were: silica (Si-MCM-41), alumino-silicate (Al-MCM-41),
and titanium-silicate (Ti-MCM-41). Our concept of promoter-assisted synthesis of zeolites and related microporous materials
was found to be applicable in the synthesis of ordered mesoporous materials as well. The addition of small catalytic quantity
of phosphate ions (PO
4
3−
), used as promoters, significantly reduced the synthesis time (by a factor of 3–4) of all these mesoporous materials. The
synthesis of new MCM-41 type organic-inorganic composite materials with unique properties is also reported. 相似文献
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In Situ Probing of the Particle‐Mediated Mechanism of WO3‐Networked Structures Grown inside Confined Mesoporous Channels 下载免费PDF全文
Lingling Zhang Jiang Li Hongjun You Chuansheng Ma Si Lan Zhenduo Wu Jianrong Zeng Feng Tian Jixiang Fang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(4)
Nanocasting, using ordered mesoporous silica or carbon as a hard template, has enormous potential for preparing novel mesoporous materials with new structures and compositions. Although a variety of mesoporous materials have been synthesized in recent years, the growth mechanism of nanostructures in a confined space, such as mesoporous channels, is not well understood, which hampers the controlled synthesis and further application of mesoporous materials. Here, the nucleation and growth of WO3‐networked mesostructures within an ordered mesoporous matrix, using an in situ transmission electron microscopy heating technique and in situ synchrotron small‐angle X‐ray scattering spectroscopy, are probed. It is found that the formation of WO3 mesostructures involves a particle‐mediated transformation and coalescence mechanism. The liquid‐like particle‐mediated aggregation and mesoscale transformation process can occur in ≈10 nm confined mesoporous channels, which is completely unexpected. The detailed mechanistic study will be of great help for experimental design and to exploit a variety of mesoporous materials for diverse applications, such as catalysis, absorption, separation, energy storage, biomedicine, and nanooptics. 相似文献
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The synthesis of SBA-15 with or without ethanol using a one-step method and its porosity were investigated. Well-ordered SBA-15 with a rod like morphology could be obtained from starting mixtures by aging at a low (60 degrees C) or high (80 degrees C) temperature in the presence of an appropriate amount of ethanol. By contrast, mesoporous materials containing aggregates of particles obtained in the absence of ethanol at high aging temperatures (70 or 80 degrees C) had complex poorly ordered structures, indicating that ethanol can affect the structure of mesoporous materials. In addition, the poorly ordered mesoporous materials had unusual desorption characteristics, namely they possessed a two-step desorption branch. 相似文献