Highly ordered mesoporous silica

Chang of synthesis temperature. For example, SBA-15 with different pore size can be obtained by changing the synthesis temperature.[27] Low temperature helps TMB to swell the micelle of FI27 and to synthesize highly ordered mesoporous silicas with very large pores.[152]... 

Highly ordered mesoporous silica can be regenerated from a mesoporous carbon CMK-3 that is a negative replica of mesoporous silica SBA-15, indicating reversible replication between carbon and inorganic materials.[193] The advantage of this synthesis method is that it does not need to make the same silica material (template). This method is likely to be a valuable complement to the existing methods for the fabrication of new mesoporous silicas and other composition materials. 

S.A. El-Safty and J. Evans, Formation of Highly Ordered Mesoporous Silica Materials adopting Lyotropic Liquid Crystal Mesophases. J. Mater. Chem. 2002, 12, 117-123. 

C.Z. Yu, Y.H. Yu, L. Miao, and D.Y. Zhao, Highly Ordered Mesoporous Silica Structures Templated by Poly(butylene oxide) Segment Di- and Tri-block Copolymers. Microporous Mesoporous Mater., 2001, 44, 65-72. 

P-ll - Secondary hydrolysis process to synthesize highly ordered mesoporous silica from nonionic surfactant with long hydrophilic chain... 

Highly ordered mesoporous silicas synthesis using deca(oxyethylene) oleylether as surfactant variation of the weight percentage of surfactant and incorporation of transition metal cations G. Herrier and B.-L. Su... 

S. Gross, G. H. Findenegg, Pore condensation in novel highly ordered mesoporous silica, Ber. Bunsenges. Phys. Chem. 101 (1991) 1726-1730. 

Figure 1). Finally, high ordered pure silica mesoporous material, containing lipase enzyme by entrapping procedure, has been obtained by sol-gel method (XRD results not showed).

This chapter deals with the selective preparation, TEM/EXAFS/XPS characterization and catalysis of mono- and bimetallic nanowires and nanoparticles highly ordered in silica FSM-16, organosilica HMM-1 and mesoporous silica thin films. The mechanism of nanowire formation is discussed with the specific surface-mediated reactions of metal precursors in the restraint of nanoscale void space of mesoporous silica templates. The unique catalytic performances of nanowires and particles occluded in mesoporous cavities are also reviewed in terms of their shape and size dependency in catalysis as well as their unique electronic and magnetic properties for the device application. 

Porous materials with chemically modified surfaces have been extensively studied as adsorbents for heavy metal ions from water (see the review by Jal et al.2 and references therein). There is a continuously growing demand for adsorbents which are non-swelling, thermally and hydrothermally stable, exhibit large adsorption capacity, fast kinetics and high affinity towards heavy metal ions. Discovery of self-assembled ordered mesoporous silicas (OMSs)3 opened enormous opportunities for the design and synthesis of highly selective and efficient adsorbents for heavy metal ions. 

O. Olkhovyk and M. Jaroniec, Ordered mesoporous silicas with 2,5-dimercapto-l,3, 4-thiadiazole ligand, high capacity adsorbents for mercury ions, Adsorption (2005) in press. 

More recently, attention has shifted to the preparation of hybrid organic-inorganic ordered mesoporous silicas, e.g. of the M41S type (see earlier), bearing pendant alkylsulfonic acid moieties [18, 91-96]. These materials combine a high... 

Ordered mesoporous silicas are of particular interest for several applications, because of highly uiuform porosity, mechanical stiffness, and thermal stability. 

Figure 10.14 shows two examples of supported nanopartides from heterogeneous catalysis. A 20wt% loading of 4nm NiO particles has been deposited inside the mesopores of SBA-15, an ordered mesoporous silica. Reduction results in highly... 

As shown in Fig. 3, nitrogen adsorption isotherms of CMK-1 feature well-pronounced capillary condensation steps similar to those of ordered mesoporous silicas and indicative of high degree of mesopore size uniformity. The isotherms reveal that the CMK-1 carbon has high nitrogen BET specific surface area (1500-1800 m g ), and large total pore volume (0.9-1.2 cm g ) [14]. The adsorption capacity is comparable or larger than that of MCM-48 template. The pore-size analysis (calibrated BJH analysis) shows that typical CMK-1 has uniform mesopores about 3 nm in size, which is accompanied by a certain amount of micropores when sucrose is used as the carbon source. 

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