Noodle-like mesoporous silica with a diameter of about 180 nm and a length of ca. 10 靘 was prepared through sol-gel process by using poly(sodium 4-styrenesulfonate) (PSS)/ cetyltrimethylammonium bromide (CTAB) comple...Noodle-like mesoporous silica with a diameter of about 180 nm and a length of ca. 10 靘 was prepared through sol-gel process by using poly(sodium 4-styrenesulfonate) (PSS)/ cetyltrimethylammonium bromide (CTAB) complex as template. Parallel oriented regular mesopores with a diameter of around 24 nm are distributed along the wall of the particles, while the 搘orm-like?disordered mesopores can be found in the fringe part. This approach provides a new series of templates and a novel route to prepare inorganic mesoporous materials with special morphology.展开更多
Ti-containing mesoporous silica materials(Ti-MSs) with isolated tetrahedrally coordinated Ti species have been widely applied in bulk molecular catalysis. Herein, Ti-MSs were synthesized using anionic surfactant SDS a...Ti-containing mesoporous silica materials(Ti-MSs) with isolated tetrahedrally coordinated Ti species have been widely applied in bulk molecular catalysis. Herein, Ti-MSs were synthesized using anionic surfactant SDS as the co-template. The SDS molecular assembled structures can interact with silica species through the interface hydrogen bonds leading to the formation of mesoporous silica structure with compact Ti-O bonds, lower hydrophilicity and low template cost. The influence of adding SDS as the co-template on the oxidation of styrene with aqueous H_2O_2 as the oxidant was investigated. Ti-MSs using SDS as the co-template showed better catalytic performance as compared with mesoporous titanium silicate synthesized with CTAB serving as the sole template. Moreover, the Ti-MSs synthesized at a Ti/Si ratio of 0.005 demonstrated an optimized performance for styrene oxidation with styrene conversion improved by 14.8%, benzaldehyde selectivity improved by 13.7% and styrene oxide selectivity improved by 9.2% when the reaction time was 6 h.展开更多
The structural and morphological properties of mesoporous silica nanoparticles( MSNs) have dramatical influence on their in vivo biological behaviors,and thereby synthesis of MSNs with well-defined shape and size has ...The structural and morphological properties of mesoporous silica nanoparticles( MSNs) have dramatical influence on their in vivo biological behaviors,and thereby synthesis of MSNs with well-defined shape and size has recently attracted much more attention in the biomedical field. The synthesis of MSNs with controllable size and shape was presented by controlling the reaction temperature and the concentration of templating agent(cetyltrimethylammonium bromide,CTAB). The results indicated that MSNs were larger in particle size and more round in shape with increasing of the reaction temperature,but their particle size and dispersivity became smaller and poorer as CTAB concentration increased. Therefore,the particle size and shape of MSNs can be tuned by using the optimal synthesis conditions for specific biomedical applications.展开更多
SSZ-39 zeolite with AEI framework structure is a good catalyst candidate for the methanol-to-olefins(MTO)reaction.However,the diffusion limitation and coke formation often results in fast deactivation of the SSZ-39 ze...SSZ-39 zeolite with AEI framework structure is a good catalyst candidate for the methanol-to-olefins(MTO)reaction.However,the diffusion limitation and coke formation often results in fast deactivation of the SSZ-39 zeolite catalyst.One solution for this challenge is to introduce mesoporosity in the SSZ-39 zeolite.Herein,we report the synthesis of mesoporous SSZ-39 zeolite using an organosilane surfactant,,-dimethyl--(3-(trimethoxysilyl)propyl)octan-1-aminium chloride,as a mesopore template and,-dimethyl--2,6-dimethylpiperidinium as a micropore template.The obtained zeolites were characterized by X-ray diffraction,N sorption,scanning electron microscopy,temperature programmed desorption of ammonia,and magic angle spinning nuclear magnetic resonance of Al.The results show that the mesoporous SSZ-39 zeolite has high crystallinity,meso/microporosity,high surface area,cuboid morphology,and abundant acidic sites.More importantly,this mesoporous SSZ-39 zeolite exhibits enhanced catalyst lifetime in the MTO reaction due to the presence of mesoporosity for fast mass transfer,compared with a conventional SSZ-39 zeolite without mesoporosity.展开更多
1 Results Ordered mesoporous materials possess enormous potential for many high-tech applications[1] such as bioreactors, microelectrophoresis, thermal insulation and catalysts. In general, organic porous materials ca...1 Results Ordered mesoporous materials possess enormous potential for many high-tech applications[1] such as bioreactors, microelectrophoresis, thermal insulation and catalysts. In general, organic porous materials can be prepared by phase-separation and hard templating approach such as those employing colloidal particles[2]. However, due to the volume contraction and swelling, and the structured defects formed during template removal, most of the resulting porous polymer structures are disordered with ...展开更多
Mesoporous titania （meso-TiO2） has received extensive attention owing to its versatile potential applications. This paper reports a low-temperature templating approach for the fabrication of meso-TiO2 using the pero...Mesoporous titania （meso-TiO2） has received extensive attention owing to its versatile potential applications. This paper reports a low-temperature templating approach for the fabrication of meso-TiO2 using the peroxo titanic acid （PTA） sol as precursor and Pluronic P123 as nonionic template. The TGA, XRD, N2 sorption, FE-SEM and HRTEM were used to characterize the obtained samples. The results showed that meso-TiO2 with high surface area up to 163 m2.g^-1 and large pore volume of 0.65 cm3.^-1 can be obtained. The mesopore sizes can be varied between 13 and 20 nm via this synthesis approach. The amount of P123 and the calcination conditions were found to have great influence on the mesoporous and crystalline structures of meso-TiO2. The photocatalytic activity testing clearly shows that the high surface area and bi-crystallinity phases of meso-TiO2 play important roles in enhancing photocatalytic properties of meso-TiO2 in photo-decomposing Rhodamine B in water.展开更多
Surfactant template synthesis of mesoporous silica monolith was carried out via modified fast sol gel process. It was easy to obtain crack free silica monolith due to low volume shrinkage during the gelation. The morp...Surfactant template synthesis of mesoporous silica monolith was carried out via modified fast sol gel process. It was easy to obtain crack free silica monolith due to low volume shrinkage during the gelation. The morphology of the titled silica was characterized by transmission electron microscopy and X ray diffraction. The results showed that the pores were worm like and the pore size was about 4 nm. Further nitrogen isothermal absorption experiment indicated that the specific area of the titled material was 391 m 2/g, which was comparable with the reported value 306 m 2/g in literature.展开更多
文摘Noodle-like mesoporous silica with a diameter of about 180 nm and a length of ca. 10 靘 was prepared through sol-gel process by using poly(sodium 4-styrenesulfonate) (PSS)/ cetyltrimethylammonium bromide (CTAB) complex as template. Parallel oriented regular mesopores with a diameter of around 24 nm are distributed along the wall of the particles, while the 搘orm-like?disordered mesopores can be found in the fringe part. This approach provides a new series of templates and a novel route to prepare inorganic mesoporous materials with special morphology.
基金financially supported by the Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents (No. 2014RCJJ017)
文摘Ti-containing mesoporous silica materials(Ti-MSs) with isolated tetrahedrally coordinated Ti species have been widely applied in bulk molecular catalysis. Herein, Ti-MSs were synthesized using anionic surfactant SDS as the co-template. The SDS molecular assembled structures can interact with silica species through the interface hydrogen bonds leading to the formation of mesoporous silica structure with compact Ti-O bonds, lower hydrophilicity and low template cost. The influence of adding SDS as the co-template on the oxidation of styrene with aqueous H_2O_2 as the oxidant was investigated. Ti-MSs using SDS as the co-template showed better catalytic performance as compared with mesoporous titanium silicate synthesized with CTAB serving as the sole template. Moreover, the Ti-MSs synthesized at a Ti/Si ratio of 0.005 demonstrated an optimized performance for styrene oxidation with styrene conversion improved by 14.8%, benzaldehyde selectivity improved by 13.7% and styrene oxide selectivity improved by 9.2% when the reaction time was 6 h.
基金National Natural Science Foundation of China(No.31271028)Shanghai Natural Science Foundation,China(No.11ZR1400100)+5 种基金Shanghai Nano Science Program,China(No.11nm0505500)Innovation Program of Shanghai Municipal Education Commission,China(No.13ZZ051)Fundamental Research Funds for the Central Universities,ChinaOpen Foundation of State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,China(No.LK1202)Chinese Universities Scientific Fund(No.13D310608)the Scientific Research Foundation for Returned Scholars,Ministry of Education of China
文摘The structural and morphological properties of mesoporous silica nanoparticles( MSNs) have dramatical influence on their in vivo biological behaviors,and thereby synthesis of MSNs with well-defined shape and size has recently attracted much more attention in the biomedical field. The synthesis of MSNs with controllable size and shape was presented by controlling the reaction temperature and the concentration of templating agent(cetyltrimethylammonium bromide,CTAB). The results indicated that MSNs were larger in particle size and more round in shape with increasing of the reaction temperature,but their particle size and dispersivity became smaller and poorer as CTAB concentration increased. Therefore,the particle size and shape of MSNs can be tuned by using the optimal synthesis conditions for specific biomedical applications.
基金the National Key Research and Development Program of China(Grant No.2017YFC0211101)the National Natural Science Foundation of China(Grant Nos.21333009,21703203 and 21673205).
文摘SSZ-39 zeolite with AEI framework structure is a good catalyst candidate for the methanol-to-olefins(MTO)reaction.However,the diffusion limitation and coke formation often results in fast deactivation of the SSZ-39 zeolite catalyst.One solution for this challenge is to introduce mesoporosity in the SSZ-39 zeolite.Herein,we report the synthesis of mesoporous SSZ-39 zeolite using an organosilane surfactant,,-dimethyl--(3-(trimethoxysilyl)propyl)octan-1-aminium chloride,as a mesopore template and,-dimethyl--2,6-dimethylpiperidinium as a micropore template.The obtained zeolites were characterized by X-ray diffraction,N sorption,scanning electron microscopy,temperature programmed desorption of ammonia,and magic angle spinning nuclear magnetic resonance of Al.The results show that the mesoporous SSZ-39 zeolite has high crystallinity,meso/microporosity,high surface area,cuboid morphology,and abundant acidic sites.More importantly,this mesoporous SSZ-39 zeolite exhibits enhanced catalyst lifetime in the MTO reaction due to the presence of mesoporosity for fast mass transfer,compared with a conventional SSZ-39 zeolite without mesoporosity.
文摘1 Results Ordered mesoporous materials possess enormous potential for many high-tech applications[1] such as bioreactors, microelectrophoresis, thermal insulation and catalysts. In general, organic porous materials can be prepared by phase-separation and hard templating approach such as those employing colloidal particles[2]. However, due to the volume contraction and swelling, and the structured defects formed during template removal, most of the resulting porous polymer structures are disordered with ...
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Grant Nos. 21201030, 21471026 and 51272039）, the Fundamental Research Funds for the Central Universities （N141005001, L1502020 and N130810003） and the Liaoning Province Innovation Funds （Grant No. 2014020030）.
文摘Mesoporous titania （meso-TiO2） has received extensive attention owing to its versatile potential applications. This paper reports a low-temperature templating approach for the fabrication of meso-TiO2 using the peroxo titanic acid （PTA） sol as precursor and Pluronic P123 as nonionic template. The TGA, XRD, N2 sorption, FE-SEM and HRTEM were used to characterize the obtained samples. The results showed that meso-TiO2 with high surface area up to 163 m2.g^-1 and large pore volume of 0.65 cm3.^-1 can be obtained. The mesopore sizes can be varied between 13 and 20 nm via this synthesis approach. The amount of P123 and the calcination conditions were found to have great influence on the mesoporous and crystalline structures of meso-TiO2. The photocatalytic activity testing clearly shows that the high surface area and bi-crystallinity phases of meso-TiO2 play important roles in enhancing photocatalytic properties of meso-TiO2 in photo-decomposing Rhodamine B in water.
文摘Surfactant template synthesis of mesoporous silica monolith was carried out via modified fast sol gel process. It was easy to obtain crack free silica monolith due to low volume shrinkage during the gelation. The morphology of the titled silica was characterized by transmission electron microscopy and X ray diffraction. The results showed that the pores were worm like and the pore size was about 4 nm. Further nitrogen isothermal absorption experiment indicated that the specific area of the titled material was 391 m 2/g, which was comparable with the reported value 306 m 2/g in literature.
