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开发并利用清洁的、可再生的能源是解决环境污染问题和能源短缺的有效方法.碳化含碳量较高的多孔有机材料制备的多孔碳,具有较高的比表面积,良好的物化稳定性,优良的机械性能等优点,在清洁能源的存储、分离、能量的存储与转化领域有广泛的应用.常见的由多孔有机材料制备多孔碳的方法主要是非活化碳化法和活化碳化法.不同的制备方法得到的多孔碳形貌,孔结构各不形同.多孔碳材料自身的结构性质可以影响其应用.合理的设计并调控多孔碳的“孔”,发挥孔尺寸的“筛分效应”可以有效地对气体进行存储和分离.在锂电等能量转化领域,“限域效应”是影响锂电性能的重要因素.多孔碳材料中较小的孔可以限域活性成分,而较大的孔可以快速传输,两种孔的协同效应可以使锂电性能大大提升.本综述系统地归纳了一步碳化多孔有机材料制备多孔碳的方法及其优势,详细地介绍了其在气体吸附、存储、分离以及电化学等领域的应用.最后,结合多孔碳材料的研究现状,提出由多孔有机材料制备多孔碳材料所面临的挑战,同时也展望了多孔碳材料的应用前景. 相似文献
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模板法制备中孔碳材料 总被引:1,自引:0,他引:1
模板法为各种中孔碳材料的可控和定向合成开辟了一条新的技术途径,近几年来已经成为国内外材料制备领域研究的热点之一.中孔碳材料具有孔道排列规则有序、孔径分布窄和比表面积高等特点而被广泛应用于气体分离、催化剂载体、吸附、色谱分析、超级电容器以及燃料电池等很多方面.本文综述了近几年来国内外模板法制备中孔碳材料的研究进展,重点阐述了模板法的种类,中孔碳材料的合成机理、方法以及中孔碳材料在生物、催化和电子能源等领域的应用,并分析了模板法制备中孔碳材料的发展趋势,认为中孔分子筛模板法和软模板法是未来制备中孔碳材料的重要方向. 相似文献
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木质素可再生资源成本低、含碳量高、芳香度高和易集中收集,被认为是具备潜力大规模工业化制备新型多孔碳材料的重要碳质原料之一,对缓解化石资源消耗及可持续发展具有重大的意义。多孔碳材料具有较高的电导率、较高的比表面积、丰富的孔道结构及良好的稳定性等特点,作为储能材料有广阔的应用前景。本文介绍了模板法、活化法及水热法制备木质素多孔碳材料的国内外最新研究进展,详细总结了不同热解工艺参数对木质素多孔碳材料微观结构的影响规律,重点阐述了其作为锂离子电池、钠离子电池和超级电容器电极材料的研究进展。针对功能化木质素多孔碳材料制备工艺复杂及储能性能差等瓶颈问题,提出离子/电子扩散动力学的优化、多种储能机制的协同作用和绿色、简便制备工艺的开发等研究策略,指出研发先进炭化技术构筑合理分级孔径结构,精准调控适宜层间距且高度有序排列碳层、功能化改性表面微环境及直接构建炭化工艺参数与电化学性能之间的因效关系是制备高储能性能木质素多孔碳材料的未来研究方向。 相似文献
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氮掺杂的多孔碳材料有望能取代当前普遍应用于质子交换膜燃料电池和金属-空气电池阴极中的贵金属氧还原催化剂,因而备受关注. 模板辅助合成技术作为一种可靠、通用的方法已经在多孔碳电催化剂的制备中得到了广泛的应用. 在碳基ORR电催化剂中,其ORR活性受到诸多因素的影响,如掺杂剂的浓度及其在碳上的分子掺杂态、孔洞结构、比表面积以及碳基材料的导电性等. 本文对近期氮掺杂多孔碳电催化剂的设计、制备、功能化及其在氧还原电催化中的应用研究进展进行了总结,同时展望了模板辅助合成法的一些发展趋势. 相似文献
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高内相比乳液模板法合成多孔材料的研究进展 总被引:1,自引:0,他引:1
综述了以高内相比乳液作模板制备多孔材料的研究进展,介绍了油包水(W/O)乳液体系法、水包油(O/W)乳液体系法和超临界CO2法等制备方法、各种多孔材料的泡孔及通道直径、比表面积、密度等性能,以及这类多孔材料在生物医学、有机化学品清除、化学催化、水溶液中固体杂质分离、液相色谱、电化学传感器等领域的应用,并对其发展前景进行了展望。 相似文献
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Jun Zheng Bing‐Hui Wu Zhi‐Yuan Jiang Prof. Qin Kuang Prof. Xiao‐Liang Fang Zhao‐Xiong Xie Prof. Rong‐Bin Huang Prof. Lan‐Sun Zheng Prof. 《化学:亚洲杂志》2010,5(6):1439-1444
Porous hollow nanostructures have attracted intensive interest owing to their unique structure and promising applications in various fields. A facile hydrothermal synthesis has been developed to prepare porous hollow nanostructures of silicate materials through a sacrificial‐templating process. The key factors, such as the concentration of the free metal cation and the alkalinity of the solution, are discussed. Porous hollow nanostructures of magnesium silicate, nickel silicate, and iron silicate have been successfully prepared by using SiO2 spheres as the template, as well as a silicon source. Several yolk–shell structures have also been fabricated by a similar process that uses silica‐coated composite particles as a template. As‐prepared mesoporous magnesium silicate hollow spheres showed an excellent ability to remove Pb2+ ions in water treatment owing to their large specific surface and unique structures. 相似文献
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以纤维素纳米晶(CNC)为模板,酚醛树脂为碳源,KOH为活化剂,通过高温碳化制备了多级孔炭材料.采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)等手段对合成的一系列炭材料进行了表征.结果表明,前驱体中CNC的降解会形成与CNC直径相当的介孔,KOH活化则会导致炭材料产生大量的微孔和大孔,以及部分4 nm左右较小尺度的介孔,所制备炭材料呈现明显的多级孔特性,其比表面积达554.7 m2/g,总孔体积为0.323 cm3/g.以CNC为模板,KOH活化的炭材料作为电极材料时,在1.0 A/g电流密度下其比电容达202.8 F/g,当电流密度升高至40.0 A/g时,其电容保持率仍达69%,表明该炭材料具有优异的倍率性能;由该电极材料组装的超级电容器在10000次充放电循环后,电容保持率达95%以上,具有良好的循环稳定性. 相似文献
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Porous carbon materials have attracted much attention in the field of organic synthesis in recent years,due to their tunable properties, excellent catalytic activity and stability. Biomass-based carbohydrates emerge as an ideal precursor for the generation of these materials owing to their renewability, low cost,non-toxicity and high content of functional groups. Thus, carbon materials prepared from carbohydrates is of considerable importance for the sustainable development of organic chemistry.... 相似文献
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Polarz S Orlov AV Schüth F Lu AH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(2):592-597
Transition-metal-oxide materials possessing ordered mesoporosity have recently attracted significant research interest due to their numerous potential applications. Among them, ordered mesoporous zinc oxide (ZnO) is a very tempting material because of the importance of ZnO in heterogeneous catalysis. Here, first results of the preparation of ordered mesoporous ZnO materials by using different templates are reported. Porous materials with high surface area, different pore sizes, and nanocrystalline ZnO walls were obtained. Furthermore, we compare the two fundamental templating techniques, involving liquid crystals or ordered mesoporous carbon materials as templates. Regarding the formation of mesoporous ZnO, it was evident that the hard-matter carbon template is superior. 相似文献
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以工业制糖的副产物糖蜜为新型碳源,替代传统多孔碳生产原料,制备出性能优异的多孔碳球超级电容器电极材料;探索了制备方法,优化了反应条件.利用全功能表面吸附仪、扫描电子显微镜及电化学方法对材料的结构、形貌和电化学性能进行了表征.结果表明,制得的多孔碳球比表面积高达2547 m~2/g,且展现出优异的双电层电容性(170.5 F/g).本研究可解决制糖企业对糖蜜无法大规模利用的问题,并为多孔碳的制备寻求新方法. 相似文献
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多孔碳材料由于高的比表面积、优异的电子传导率、良好的化学稳定性等优点在超级电容器电极材料领域被广泛研究。 碳材料的组成及表面孔结构直接影响其电化学性能,为进一步提高碳材料的电容性能,本文首次以聚多巴胺球为前体,KOH为活化剂,通过高温碳化成功制备了良好电化学性能的氮掺杂多孔碳材料。 通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、 X射线粉末衍射(XRD)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)和Raman光谱等对所制备的氮掺杂多孔碳材料进行了形貌及结构组成的表征。 在6 mol/L KOH电解液中, 采用循环伏安、恒电流充放电对多孔碳材料的电化学性能进行了研究。 结果表明,由于双电层电容和赝电容的协同作用,在电流密度为1 A/g时,材料的比电容可达269 F/g,充放电循环1000圈后电容仍可保留初始值的93.5%。 相似文献
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Porous graphite-phase polymeric carbon nitride (GPPCN)/TiO2 donor-acceptor heterojunction was facilely fabricated through the combination of a template technique with a co-calcination process, which exhibited much higher photoelectric activity compared to pristine carbon nitride and TiO2. The precursor of porous GPPCN (pGPPCN), porous melem, was prepared by using a green template, calcium carbonate, which could be easily removed by diluted hydrochloride. The pGPPCN/TiO2 heterojunction was then obtained by the assembly and subsequent co-calcination of TiO2 nanoparticles with porous melem. The formation of pGPPCN/TiO2 donor-acceptor heterojunction prepared by this method showed improved surface area and light absorption. Moreover, the composite presented much higher photo-energy conversion activity than those of GPPCN, pGPPCN and TiO2, which could be mainly ascribed to the high charge carrier separation efficiency. This study provides a new approach for the design and development of various photocatalysts with high efficiency for applications in energy fields. 相似文献
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Porous sulfonic acid functionalized silica spheres have been prepared by oxidation ofthiol-functionalized mesoporous silica samples obtained by co-condensation of (mercaptopropyl)trimethoxysilane and tetraethoxysilane in the presence ofcetyltrimethylammonium as a template. The physicochemical characteristics of the resulting ion exchangers have been analyzed by various techniques and discussed with respect to the amount of functional groups in the materials. Their ion exchange behavior was then studied from batch experiments (determination of cation exchange capacities) and by electrochemistry at carbon paste electrodes modified with these solids. In particular, ion exchange voltammetry applied to two model electroactive cations, Cu2+ and Ru(NH3)6(3+), has pointed out the key role played by the content of organofunctional groups in the materials (which strongly affects their structure and porosity) on their performance as electrode modifiers for preconcentration of target analytes prior to electrochemical detection. 相似文献