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preparation of Chiral Silica Nanostructures with Radial Pores through Single-templating Approach

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1293-1298页

作者： ZHA Xinlin FAN Hui CHEN Yuanli Key Laboratory of Textile Fiber and Products(Wuhan Textile University) Ministry of EducationWuhan 430073China

A chiral low-molecular-weight gelator(LMWG) L-16Ala5PyPF6 was synthesized from L-alanine, which can cause physical gel in n-propanol, ethyl acetate, butylene oxide, water, benzene, 1,4-dioxane and chloroform. The sol-gel reactions were carried out in a mixture of stronger ammonia water and n-propanol at the volume ratio of 2:8. Single-handed twisted silica nanostructures with pore channels vertical to the wall surfaces were first prepared through a single-templating approach comparing with the reported double template method. The formation mechanism of radial pore structure was studied by transmission electron microscopy at different reaction time intervals, which indicated that the radial pore structure was formed via a structural transition in the sol-gel transcription process.

关键词： sol-gel preparation radial pores vertical pore channels single-handed structural transition

preparation of Silica Nanosphere with Vertical Pore and Its Application in Oil-water Separation

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Journal of Wuhan University of Technology(Materials Science) 2023年第2期38卷 299-303页

作者： FAN Hui CAI Yun BAI Ping YUAN Qinwen WANG Dong CHEN Yuanli State Key Laboratory of New Textile Materials and Advanced Processing Technologies of China Key Laboratory of Textile Fiber and ProductsMinistry of EducationHubei International Scientific and Technological Cooperation Base of Intelligent Textile Materials&ApplicationWuhan Textile UniversityWuhan430200China

Uniform monodispersed mesoporous silica nanospheres with vertical pores were successfully synthesized using chiral amphiphilic small molecule L-16Ala5PyClO4and solvents as dual templates via solgel *** morphologies and pore sizes of silicas are adjustable by changing the type and amount of solvents in the reaction *** the increase of the organic solvent content,the morphologies of the obtained silica changed from nanospheres with vertical pore structures to nanosheets *** 1 mL of benzene,cyclohexane or toluene were used as solvents,only silica nanospheres were obtained,the BET surface areas of silica nanospheres reached 600.7,669.5,and 560.8 m^(2)/g,*** pore sizes were 3.51,3.54,and 3.46 nm,***,these ordered silica nanospheres/poly(vinyl alcohol-co-ethylene)(PVAco-PE)nanofiber membranes have high separation efficiencies(>99%)for n-hexane/water mixtures.

关键词： sol-gel preparation mesoporous silica nanosphere oil-water separation

Facile and controllable preparation of mesoporous TiO2 using poly（ethylene glycol） as structure-directing agent and peroxotitanic acid as precursor

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Frontiers of Materials Science 2016年第4期10卷 405-412页

作者： Dongthanh NGUYEN Wei WANG Haibo LONG Hongqiang RU Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) School of Materials Science and Engineering Northeastern University Shenyang 110819 China

This work demonstrated that mesoporous TiO= （meso-TiO2） with con- trollable mesoporous and crystalline structures can be facilely prepared by using poly （ethylene glycol）（PEG） as structure-directing （SD） agent and peroxotitanic acid （PTA） as precursor. Meso-TiO2 with high specific surface area （157 m2.g-1）, pore volume （0.45 cm3.g-1） and large mesopore size of 13.9 nm can be obtained after calcination at 450℃. Such meso-TiO2 also shows relatively high thermal stability. BET surface area still reaches 114 m2-g-1 after calcination at 550℃. In the synthesis and calcination process, PEG that plays multiple and important roles in delivering thermally stable and tunable mesoporous and crystalline structures shows to be a suitable low-cost SD agent for the controllable preparation of nanocrystalline meso-TiO2. The photocataiytic activity tests show that both high surface area and bi-crystallinity of obtained meso-TiO2 are important in enhancing the performance in photo-decomposing Rhodamine B in water.

关键词： sol-gel preparation mesoporous titania poly(ethylene glycol)

preparation and characterization of helical carbon/silica nanofibers with lamellar mesopores on the surfaces

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Chinese Chemical Letters 2014年第2期25卷 253-256页

作者： Qing Wang Bao-Zong Li Yi Li Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow University

Helical 1,2-ethylene-silica nanofibers with lamellar mesopores on the surfaces and twisted rod-like mesopores inside were prepared according to literature procedures. After carbonization, helical carbon/ silica nanofibers with lamellar mesopores on the surfaces and twisted rod-like micropores inside were obtained. The morphologies and pore architectures of the carbon]silica nanofibers were characterized using transmission electron microscopy, field-emission scanning electron microscopy, powder X-ray diffraction and N2 sorptions. Although the mesopores inside shrank into micropores, the helical nanostructure remained. Moreover, several carbon/silica nanofibers with lamellar mesopores on the surfaces and concentric circular micropores inside were also obtained. After being calcined in air, helical silica nanofibers with lamellar mesopores on the surfaces and twisted rod-like micropores inside were produced as well.

关键词： Nanoparticles Mesoporous Carbon/silica sol-gel preparation Structural

Fabrication, Sintering and Electrical Properties of (Ca_(0.61),Nd_(0.26))TiO_3 Nanoparticles Doped with Li-Cu-B

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Journal of Materials Science & Technology 2011年第5期27卷 426-430页

作者： Fei Wu Qilong Zhang Hui Yang Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

A sol-gel processing was used to low temperature. Orthorhombic synthesize （Cao.61,Ndo.26）TiO3 （CNT） perovskite structure phase with a smal nanoparticles doped with Li-Cu-B at amount of Li3BO3 secondary phase was formed by calcining the xerogels at 300℃, and monodisperse CNT nano-powders with the grain size of 10-15 nm could be obtained. By using these nanocrystalline CNT powders, dense CNT ceramics could be achieved at the low sintering temperature of 1100℃ due to the effect of the small size nanoparticles and liquid phase Li3BO3. And the dielectric properties with dielectric constant （εr= 89.52）, quality value factors with frequency （Q×f=17148 GHz） and the temperature coefficient of resonant frequency （τf） value of ＋239×10^-6/℃ were achieved.

关键词： sol-gel preparation Nanomaterials Electrical properties Sintering

Fabrication of Porous Silica Microspheres Under the Assistance of solid Template

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Chemical Research in Chinese Universities 2012年第3期28卷 546-554页

作者： MAO Zheng-wei HU Ling ZHAO Qing-he GAO Chang-you Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of EducationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027P.R.China

Spherical porous silica microparticles were synthesized by a sol-gel process in the presence of porous CaCO3 particles, followed by removal of the carbonate templates. The resulting silica particles had very high porosity and wide pore size distribution, whose surface area and pore volume reached up to 367.3 m2/g and 0.72 mL/g, re- spectively. With a larger amount of the tetraethyl orthosilicate used, hollow silica microspheres were further obtained. Characterization was made to confirm the chemical and physical structures and purity of the silica microspheres. Spontaneous deposition of tetramethyl rhodamine isothiocyanate labeled dextran into the microspheres was also ob- served due to the charge attraction.

关键词： Porosity Deposition sol-gel preparation Silicone dioxide Microsphere

Mechanism of upconversion emission enhancement in Y_3Al_5O_(12):Er^(3+)/Li^+ powders

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Journal of Rare Earths 2011年第11期29卷 1022-1025页

作者：杨明珠隋郁牟海维吕树臣王先杰吕天全 College of Electronic Science Northeast Petroleum University Center for Condensed Matter Science and Technology(CCMST) Department of PhysicsHarbin Institute of Technology International Center for Materials Physics Academia Sinica Department of Physics Harbin Normal University

Er3＋ and Li＋ codoped Y3Al5O12（YAG） powders were prepared for a systematic investigation of their upconversion emissions.X-ray diffraction（XRD）,upconversion emission spectra,pump power dependence,FT-IR spectra and decay time were studied to characterize the *** Li＋ doping,the upconversion emission intensity of Er3＋ doped YAG powders was obviously enhanced,accompanied with an increase in the ratio of green to red *** enhancement of emission intensity could be attributed to two mechanisms：one was the distortion of local crystal field around Er3＋,and the other was the decrease in the amount of CO32-and *** results revealed that the latter was the dominant mechanism of the upconversion intensity enhancement in the YAG：Er3＋/Li＋ powders.

关键词： luminescence optical materials and properties sol-gel preparation nanomaterials rare earths

Luminescent properties of amorphous phosphor 1.4Y_2O_3·2.5Al_2O_3·0.1Tb_2O_3 prepared by sol-gel method

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Journal of Rare Earths 2008年第1期26卷 35-39页

作者：李秀娟余泉茂曾正志荆西平 College of Chemistry and Chemical Engineering Lanzhou University Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular EngineeringPeking University Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University

Amorphous phosphor 1.4YeO3·2.5Al2O3·0.1Tb2O3 （the same composition as Y2.8Tb0.2Al5O12） was prepared via a sol-gel method at relatively low temperature （i.e., below 650℃）, which is much lower than that for the preparation of polycrystalline Y3Al5O12：Tb^3＋（above 1400℃）. The amorphous phosphor prepared in the optimized conditions showed a bright green-yellowish luminescence, the intensity of which was comparable with that of polycrystalline sample and the emissions of which were assigned to 5D4 → 7Fj transitions of Tb^3＋. Besides the emissions of Tb^3＋, the amorphous samples prepared at temperatures below 500 ℃ presented a weak blue emission band around 420 nm.

关键词： amorphous sol-gel preparation luminescence YAG:Tb rare earths

Effect of La Doping on Microstructure and Ferroelectric Prop-erties of Bi_4Ti_3O_(12) Thin Films Prepared by sol-gel Method

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Journal of Wuhan University of Technology(Materials Science) 2008年第5期23卷 622-624页

作者：付承菊 School of Material Science and Engineering Wuhan University of Technology

The Bi4Ti3Oi2 and Bi3.25La0.75Ti3O12 thin films were prepared on the Pt/Ti/SiO2/Si substrate using the sol-gel method. The effect of La doping on the microstructure and ferroelectric properties of Bi4Ti3O12 films were investigated. Both the Bi4Ti3O12 and Bi3.25La0.75Ti3O12 thin films exhibited typical bismuth layered perovskite structure. The 2Pr （remanent polarization） value of Bi3.25La0.75Ti3O12 thin films is 18.6 μC/cm^2, which is much larger than that of Bi4Ti3O12 thin films. And the Bi3.2eLa0.75Ti3O12 films show fatigue-free behavior, while the Bi4Ti3O12 thin films exhibit the fatigue problem. The mechanism of improvement of La doping was discussed.

关键词： ferroelectric properties sol-gel preparation Bi4Ti3O12 thin films Bi3.25La0.75Ti3O12 thin films La doping fatigue