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Synthesis of Mesoporous TiO2 Using Gemini Surfactant at Room Temperature
DENG Feng-Ping,LI Yue,QI Xing-Hong,WU Sheng-Yan,ZHANG Wen-Hui
无机材料学报 , 2009, DOI: 10.3724/sp.j.1077.2009.00039
Abstract: Using Gemini231 quaternary ammonium salts cationic surfactant as template, mesoporous titanium dioxide material was synthesized by sol-gel method at room temperature. The synthesized samples were investigated by thermogravimetic-differential thermal analysis, X-ray diffraction, nitrogen adsorption-desorption and transmission electron microscope(TEM) techniques. The results show that the obtained mesoporous TiO2 calcined at 480 ave a high specific surface area up to a 383.8m2 ¤g1 , and a mean pore size of about 5.8nm in diameter, and crystallized anatase framework. No rutile phase is found. Small-angle X-ray diffraction analysis shows that the sample has an ordered mesoporous structure.a¤
Recent Progress in Preparation of Ordered Mesoporous Film
SU Bin,LU Xue-Min, LU Qing-Hua
无机材料学报 , 2007,
Abstract: The film containing oriented mesochannels in uniform direction at large scales can be defined as ordered mesoporous thin film. Various preparation methods of ordered mesoporous silica thin films are reviewed in recent years. These preparation methods can be summarized into three kinds in mechanism. The factors influencing the mesoporons film preparation are also discussed and analyzed based on the viewpoint of 'order'. In addition, the progress tendencies of those preparation methods in the future are also introduced.
Ordered mesoporous silica carrier system applied in nanobiothecnology
Sousa, Andreza de;Sousa, Edésia Martins Barros de;
Brazilian Archives of Biology and Technology , 2005, DOI: 10.1590/S1516-89132005000700036
Abstract: ordered mesoporous materials like sba15 possess a network of channels and pores of well-defined size in the nanoscale range (2-50 nm). this particular pore architecture makes them suitable candidates for hosting and delivery under appropriate conditions of a variety of molecules of pharmaceutical interest, including radiopharmaceuticals. the characteristics of sba-15 prepared in different temperatures and the behavior of this system regarding microencapsulation of a model drug were investigated. the calcined samples were formed in 0.2 g disks and were soaked in a solution of atenolol used as a model drug. the modification of the aging temperature provoked changes in the structure of the pores, indicating the presence of microporosity and connections between mesopores. aging the materials at a higher temperature resulted in no microporosity and this fact influenced the control of the release of the model drug.
Investigation on the Textural Properties Tuning of Ordered Mesoporous Carbons with an Excellent Electrochemical Performance  [PDF]
Pavuluri Srinivasu
Advances in OptoElectronics , 2011, DOI: 10.1155/2011/615164
Abstract: A synthetic method to produce mesoporous carbons with tunable textural properties and ordered pore structure has been developed by changing sucrose to water ratio. The specific surface area of 1437?m2/g with pore volume of 1.4?cm3/g and porosity of mesopores centered at around 4.4?nm are achieved by tuning the concentration of filling amount into mesoporous silica. The mesoporous carbon exhibits hexagonal rod-like morphology (a diameter of ~1.2? m), which confirms that the replication process is highly successful. It is demonstrated that the prepared mesoporous carbon exhibits much higher current density and superior performance as compared to conventional activated charcoal. 1. Introduction Ordered mesoporous carbons have attracted considerable attention in the past few years due to their applications in adsorption of larger molecules, electrochemical double layer capacitor, catalyst support, fuel cells, solar cells, and hydrogen storage systems [1–6]. These kinds of applications require porous carbon with tailored porous structure [7, 8]. Recently, several different methods have been developed to synthesize mesoporous carbons. These include the carbonization of polymer aerogels such as resorcinol-formaldehyde resins [9], the catalytic activation of carbon precursors in the presence of metals and organometallic compounds [10, 11], and carbonization of polymer blends with thermally unstable components [12, 13]. However, these methods result in having a mesoporous carbon with broad pore size distribution. Among them, template synthesis method [14–17] has been extensively used due to the obtained material possessing uniform and interconnected pores. The synthesis technique is known as “nanocasting.” This synthetic technique involves impregnation of silica template with an appropriate carbon source, carbonization of carbon precursor, and subsequent removal of silica. The resulting carbons are inverse replicas of ordered mesoporous silicas. Since the first successful synthesis of ordered mesoporous carbon (CMK-1) using MCM-48 [14], various structures have been reported from different silica templates. On the other hand, textural parameters such as surface area, pore volume, and pore diameter are found to be significantly influencing the electrocatalytic activity. In supported materials, mesoporous offers high metal dispersion and stability of nanoparticles. Although tuning the textural properties of mesoporous carbon is important for various catalytic and electrocatalytic studies, the effect of sucrose concentration on tuning the properties of mesoporous
Pore Structure Control of Ordered Mesoporous Silica Film Using Mixed Surfactants
Tae-Jung Ha,Hyeon-Gyoon Im,Seok-Jin Yoon,Ho Won Jang,Hyung-Ho Park
Journal of Nanomaterials , 2011, DOI: 10.1155/2011/326472
Abstract: Materials with nanosized and well-arranged pores have been researched actively in order to be applied to new technology fields. Especially, mesoporous material containing various pore structures is expected to have different pore structure. To form a mixed pore structure, ordered mesoporous silica films were prepared with a mixture of surfactant; Brij-76 and P-123 block copolymer. In mixed surfactant system, mixed pore structure was observed in the region of P-123/(Brij-76
Synthesis and Characterization of Ordered Mesoporous Zirconium-doped Silica with Strong Acidity  [PDF]
DENG Jun,ZHANG Hong-sheng,FU Wen-sheng
Journal of Chongqing Normal University , 2011,
Abstract: A series of mesoporous sulfated silica-zirconia materials with various Si/Zr molar ratios(2.0-5.0) have been prepared using stri-block copolymer as a template, which was characterized by X-ray diffraction, TEM, nitrogen adsorption-desorption, UV-Vis diffuse reflectance spectroscopy, infrared spectroscopy, thermal gravimetric analysis, and catalytic reactions. XRD patterns displayed that ordered mesoporous sulfated silica-zirconia materials were obtained when the molar ratio of Si/Zr was more than 4.0. When the molar ratio of Si/Zr was less than 4.0, the samples had a separated phase of amorphous sulfated zirconia. Furthermore, TEM images revealed that the mesostructure of these materials were highly ordered. N2 adsorption exhibited typical IV adsorption-desorption isotherms and uniform pore distribution. UV-Vis reflectance, and IR spectra suggested that Zr atoms were incorporated into the walls of mesoporous silica. Cracking reactions of cumene and 1,3,5 -triisopropylbenzene(TIPB) showed that, the ordered mesoporous sulfated silica-zirconia materials were very active in acidic catalytic reactions, especially for the cracking of large molecules.
Electrochemical Hydrogen Storage in a Highly Ordered Mesoporous Carbon  [PDF]
Haolin Tang,Dong Zheng,Deyu Qu,Zhizhong Xie,Deyang Qu
Frontiers in Energy Research , 2014, DOI: 10.3389/fenrg.2014.00042
Abstract: A highly ordered mesoporous carbon (HOMC) has been synthesized through a strongly acidic, aqueous cooperative assembly route. The structure and morphology of the carbon material were investigated using TEM, SEM, and nitrogen adsorption–desorption isotherms. The carbon was proven to be meso-structural and consisted of graphitic micro-domain with larger interlayer space. Active carbon impedance and electrochemical measurements reveal that the synthesized highly ordered mesoporous carbon (HOMC) exhibits a promoted electrochemical hydrogen insertion process and improved capacitance and hydrogen storage stability. The meso-structure and enlarged interlayer distance within the HOMC are suggested as possible causes for the enhancement in hydrogen storage. Both hydrogen capacity in the carbon and mass diffusion within the matrix were improved.
Template Synthesis of Three-Dimensional Cubic Ordered Mesoporous Carbon With Tunable Pore Sizes  [cached]
Dai Weijie,Zheng Mingbo,Zhao Yu,Liao Shutian
Nanoscale Research Letters , 2009,
Abstract: Three-dimensional cubic ordered mesoporous carbons with tunable pore sizes have been synthesized by using cubic Ia3d mesoporous KIT-6 silica as the hard template and boric acid as the pore expanding agent. The prepared ordered mesoporous carbons were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption–desorption analysis. The results show that the pore sizes of the prepared ordered mesoporous carbons with three-dimensional cubic structure can be regulated in the range of 3.9–9.4 nm. A simplified model was proposed to analyze the tailored pore sizes of the prepared ordered mesoporous carbons on the basis of the structural parameters of the silica template.
Rapid removal of bisphenol A on highly ordered mesoporous carbon

Qian Sui,Jun Huang,Yousong Liu,Xiaofeng Chang,Guangbin Ji,Shubo Deng,Tao Xie,Gang Yu,

环境科学学报(英文版) , 2011,
Abstract: Bisphenol A (BPA) is of global concern due to its disruption of endocrine systems and ubiquity in the aquatic environment. It is important, therefore, that e orts are made to remove it from the aqueous phase. A novel adsorbent, mesoporous carbon CMK-3, prepared from hexagonal SBA-15 mesoporous silica was studied for BPA removal from aqueous phase, and compared with conventional powdered activated carbon (PAC). Characterization of CMK-3 by transmission electron microscopy (TEM), X-ray di raction, and nitrogen adsorption indicated that prepared CMK-3 had an ordered mesoporous structure with a high specific surface area of 920 m2/g and a pore-size of about 4.9 nm. The adsorption of BPA on CMK-3 followed a pseudo second-order kinetic model. The kinetic constant was 0.00049 g/(mg min), much higher than the adsorption of BPA on PAC. The adsorption isotherm fitted slightly better with the Freundlich model than the Langmuir model, and adsorption capacity decreased as temperature increased from 10 to 40°C. No significant influence of pH on adsorption was observed at pH 3 to 9; however, adsorption capacity decreased dramatically from pH 9 to 13.
Ultrasonic―hydrothermal Synthesis and Photocatalytic Activities of La―doped Mesoporous TiO2 Microspheres
LIU Guo-Cong, LI Hai-Bin, DONG Hui
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.00739
Abstract: With tetrabutyl orthotitanate (TBOT) as Ti source, La(NO3)3·6H2O as La source and octadecylamine as a template, La―doped mesoporous TiO2 microspheres were prepared by ultrasonic―hydrothermal method. The obtained samples were characterized by XRD, XPS, TEM, BET, UV―Vis, IR and FL.The results revealed that the appropriate molar fraction of La dopant could decrease crystalline size, increase specific surface area and weaken fluorescence intensity of mesoporous TiO2. Compared with P25, the gap adsorption edge of mesoporous La3+/TiO2 exhibited a little red shift and slightly narrowed their band gaps. For mesoporous La3+/TiO2 (2.0 at%), the specific surface area and the average pore diameter were 132.7 m2/g and 8.67 nm, respectively. Furthermore, the degradation ratio of methylene blue to mesoporous La3+/TiO2 (2.0at%) was up to 98.5%, which exhibited the best photocatalytic activity with the initial concentration of 40 mg/L for 120 min.
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