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以尿素-过氧化氢为混合模板、正硅酸乙酯为硅源,在酸性条件下,通过溶胶-凝胶过程合成二氧化硅介孔材料。采用煅烧法除去模板剂,用红外光谱、XRD、N2吸附-脱附、HRTEM等分析测试手段对介孔材料的结构和形态进行了表征。结果表明:与以尿素为单一模板相比,采用混合模板剂所合成介孔材料为蠕虫状,孔径分布基本保持不变、比表面积相近(分别为445、431m2/g)、孔径(分别为7.04、8.11nm)和孔体积(分别为0.783、0.874cm3/g)明显增大。 相似文献
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以一种新碳前驱体制备有序介孔碳及其表征 总被引:1,自引:1,他引:0
分别采用两亲性三嵌段共聚物F127、P123以及F127/P123复合物为模板剂,线性酚醛树脂/六亚甲基四胺固化物为碳源,利用有机-有机自组装法制备了具有二维六方结构和蠕虫状结构的介孔碳材料。采用FT-IR、XRD、TEM、低温N2吸附/脱附、TG和元素分析等方法表征了介孔碳的结构,研究了不同的模板剂对介孔碳结构的影响。结果表明,以F127为模板剂制备的介孔碳具有规则的二维六方结构,其比表面积、微孔表面积、孔容、孔径和孔壁厚度分别为670m2/g、368m2/g、0.40cm3/g、3.2nm和4.5nm。以P123为模板剂制备的介孔碳具有蠕虫状结构,其比表面积、微孔表面积、孔容和孔径分别为506m2/g、251m2/g、0.27cm3/g和3.0nm。以F127/P123复合物为模板剂制备的介孔碳的孔径相对于单一模板剂有所提高,其比表面积、微孔表面积、孔容和孔壁厚度均随着复合模板剂中F127质量分数的降低而降低。 相似文献
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三嵌段共聚物F127为模板剂,线性酚醛树脂为碳前驱体,采用溶剂挥发诱导有机-有机自组装法(EI-SA)制备了具有二维六方结构的有序介孔碳。利用FT-IR、XRD、TEM、N2吸附/脱附等方法对有序介孔碳的结构进行了表征,研究了不同焙烧温度和模板剂用量对有序介孔碳结构的影响。结果表明,当模板剂的用量一定时,有序介孔碳的孔径、孔容和孔壁厚度都随着焙烧温度的升高而降低,但比表面积却随着微孔含量的增加而增大。随着模板剂用量的增加,介孔碳的有序性降低。有序介孔碳PF-2-500的比表面积、孔径、孔容、孔壁厚度和微孔比表面积比分别为583.82m2/g、3.05nm、0.31cm3/g、3.40nm和361.18m2/g,而有序介孔碳PF-1-500的比表面积、孔径和孔容相对于PF-2-500有所提高,分别为647.79m2/g、3.44nm和0.41cm3/g,但微孔比表面积和孔壁厚度分别降低为309.46m2/g和3.35nm。 相似文献
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以醇铝为原料,利用三种不同类型的模板剂对氧化铝的孔径进行调节,对各种模板剂的作用机理进行了初步探讨.研究结果表明:不同模板剂获得的介孔氧化铝的孔道结构基本一致,均为蠕虫状结构,模板剂的不同对介孔氧化铝孔径的影响较大,未加模板剂直接由溶胶-凝胶法获得的介孔氧化铝孔径分布较窄,孔径偏小;加入离子型模板剂能够形成孔径分布窄、孔径增大的介孔材料;加入非离子型模板剂则形成孔径更大,但孔径分布较宽的介孔氧化铝. 相似文献
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首先合成了一种新型双功能性离子液体1-甲基-3-(3'-磺酸丙基)咪唑十二烷基磺酸盐([PMIM(SO3H)][C12SO3]),并采用FT-IR、1H NMR和13C NMR对其结构进行了表征;进一步以该离子液体为模板剂和酸源,以正硅酸乙酯(TEOS)为硅源,通过溶胶-凝胶法制备出介孔SiO2,利用TGA和FT-IR研究了介孔材料的形成过程,采用SAXRD、SEM、TEM和氮气等温吸附-脱附等手段对介孔材料的结构形貌进行了表征,并研究了其对Pb2+的吸附性能。结果显示,以[PMIM(SO3H)][C12SO3]为模板剂和酸源制备的介孔SiO2其比表面积、孔容、平均孔径大小分别为1 010m2/g、0.95 cm3/g、3.25 nm,其对重金属Pb2+有很好的吸附性能。 相似文献
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Interests are focused on preparation of hierarchical porous materials with zeolite structures by using soft or rigid templates in order to solve diffusion and mass transfer limitations resulting from the small pore sizes of zeolites. Here we develop a convenient template-free sol–gel method to synthesize hierarchical porous materials with ZSM-5 structures. This method involves hydrothermal recrystallization of the xerogel converted from uniform ZSM-5 sol by a vacuum drying process. By utilizing this method we can manipulate the size of zeolite nanocrystals as building units of porous structures based on controlling temperature of recrystallization, consequently obtain hierarchical porous materials with different intercrystalline pore sizes and ZSM-5 structures. 相似文献
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Bing ZhaoJinsong Song Tao FangPeng Liu Zheng JiaoHaijiao Zhang Yong Jiang 《Materials Letters》2012,67(1):24-27
Porous NiO nanosheet has been synthesized by hydrothermal method, using Ni(NO3)2·6H2O and urea as the raw materials and DI water as solvent, then followed by calcination process. It has been indicated by TEM and BET analysis that the as-prepared NiO was porous nanosheet. With the increase of annealing temperature, the pore size on the nanosheet becomes larger and the specific surface area becomes much smaller. All isotherms of NiO display type IV with H3 type hysteresis loop with pore size distribution of 2-60 nm. The annealing temperature turns out to be the key factor to pore size, pore distribution and pore volume. 相似文献
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多孔微晶玻璃具有导热系数低、力学性能好、抗腐蚀性强等优点,是一种隔热、吸声的轻质功能材料。为拓展多孔微晶玻璃的制备原料范围,同时大宗量、高附加值利用工业废渣-磷渣和煤矸石。本文以磷渣和煤矸石为原料,采用烧结法制备多孔微晶玻璃。利用X射线衍射、扫描电子显微镜及阿基米德法,对制备的试样进行表征,研究发泡剂碳酸钙掺量对体系析晶、发泡和宏观性能的影响。研究表明,碳酸钙掺量不影响体系析晶相的种类,但体系析晶度随碳酸钙掺量增加先增大后减小;碳酸钙掺量为2%~6%(质量分数)时,增大掺量,利于发泡。体系中气孔孔径增大且趋于均匀,试样孔隙率增大,体积密度降低。但随着掺量进一步增大,体系发泡效果降低。当碳酸钙掺量为4%~8%(质量分数)时,可获得体积密度为0.86~0.92 g/cm3,孔隙率为60.7%~70.3%,抗压强度为7.89~15.11 MPa,性能较优的硅灰石多孔微晶玻璃。本研究以工业废渣为原料,降低了多孔微晶玻璃的制备成本,同时为工业废渣利用提供一种途径借鉴,具有深远的资源和环保意义。 相似文献
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采用NaY沸石分子筛作模板,乙酰丙酮为炭前驱体,使用液相浸渍-气相沉积工艺合成了富含微孔和中孔结构的多孔炭材料并对其进行了表征.所合成的多孔炭比表面积1351m2/g,孔容0.892cm3/g,微孔率0.63,孔径分布多在0.8nm~3.0nm之间. 相似文献
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Preparation of porous alumina abrasives and their chemical mechanical polishing behavior 总被引:1,自引:0,他引:1
Porous alumina abrasives with different pore sizes were prepared using hydrothermal synthesis method by different hydrothermal temperatures. The pore structure, pore size and pore volume of the products were characterized by transmission electron microscopy and nitrogen adsorption desorption isotherm measurement. The chemical mechanical polishing (CMP) performances of porous alumina abrasives in hard disk substrate CMP were investigated. The results show that, the polished surface average roughness (Ra) decreases when the pore diameter of porous alumina abrasive increases. By comparison with solid alumina abrasive, the prepared porous alumina abrasives give lower Ra, and the porous alumina abrasive with 8.61 nm pore diameter has higher material removal rate under the same polishing conditions. 相似文献
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Facile fabrication of hierarchically porous carbonaceous monoliths with ordered mesostructure via an organic organic self-assembly 总被引:1,自引:0,他引:1
A simple strategy for the synthesis of macro-mesoporous carbonaceous monolith materials has been demonstrated through an organic-organic
self-assembly at the interface of an organic scaffold such as polyurethane (PU) foam. Hierarchically porous carbonaceous monoliths
with cubic (Im
m) or hexagonal (p6mm) mesostructure were prepared through evaporation induced self-assembly of the mesostructure on the three-dimensional (3-D)
interconnecting struts of the PU foam scaffold. The preparation was carried out by using phenol/formaldehyde resol as a carbon
precursor, triblock copolymer F127 as a template for the mesostructure and PU foam as a sacrificial monolithic scaffold. Their
hierarchical pore system was macroscopically fabricated with cable-like mesostructured carbonaceous struts. The carbonaceous
monoliths exhibit macropores of diameter 100–450 μm, adjustable uniform mesopores (3.8–7.5 nm), high surface areas (200–870
m2/g), and large pore volumes (0.17–0.58) cm3/g. Compared with the corresponding evaporation induced self-assembly (EISA) process on a planar substrate, this facile process
is a time-saving, labor-saving, space-saving, and highly efficient pathway for mass production of ordered mesoporous materials.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.
This article is published with open access at Springerlink.com 相似文献