Zeolites are a family of crystalline aluminosilicate materials widely used as shape-selective catalysts, ion exchange materials, and adsorbents for organic compounds. In the present work, zeolites were synthesized by adding a rationally designed amphiphilic organosilane surfactant to conventional alkaline zeolite synthesis mixtures. The zeolite products were characterized by a complementary combination of X-ray diffraction (XRD), nitrogen sorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The analyses show that the present method is suitable as a direct synthesis route to highly mesoporous zeolites. The mesopore diameters could be uniformly tailored, similar to ordered mesoporous silica with amorphous frameworks. The mesoporous zeolite exhibited a narrow, small-angle XRD peak, which is characteristic of the short-range correlation between mesopores, similar to disordered wormhole-like mesoporous materials. The XRD patterns and electron micrographs of the samples taken during crystallization clearly showed the evolution of the mesoporous structure concomitantly to the crystallization of zeolite frameworks. The synthesis of the crystalline aluminosilicate materials with tunable mesoporosity and strong acidity has potentially important technological implications for catalytic reactions of large molecules, whereas conventional mesoporous materials lack hydrothermal stability and acidity.

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Among various nanoparticles, the silica nanoparticle (SiNP) is an attractive candidate as a gene delivery carrier due to advantages such as availability in porous forms for encapsulation of drugs and genes, large surface area to load biomacromolecules, biocompatibility, storage stability, and easy preparation in large quantity with low cost. Here, we report on a facile synthesis of monodispersed mesoporous silica nanoparticles (MMSN) possessing very large pores (>15 nm) and application of the nanoparticles to plasmid DNA delivery to human cells. The aminated MMSN with large pores provided a higher loading capacity for plasmids than those with small pores (∼2 nm), and the complex of MMSN with plasmid DNA readily entered into cells without supplementary polymers such as cationic dendrimers. Furthermore, MMSN with large pores could efficiently protect plasmids from nuclease-mediated degradation and showed much higher transfection efficiency of the plasmids encoding luciferase and green fluorescent protein (pLuc, pGFP) compared to MMSN with small pores (∼2 nm).

A coordination-assisted synthetic approach is reported here for the synthesis of highly active and stable gold nanoparticle catalysts in ordered mesoporous carbon materials using triblock copolymer F127 as a structure-directing agent, thiol-containing silane as a coordination agent, HAuCl4 as a gold source, and phenolic resin as a carbon source. Upon carbonization, the gold precursor becomes reduced to form monodispersed Au nanoparticles of ca. 9.0 nm, which are entrapped or confined by the "rigid" mesoporous carbonaceous framework. Nanoparticle aggregation is inhibited even at a high temperature of 600 °C. After removal of the silica component, the materials possess the ordered mesostructure, high surface area (~1800 m(2)/g), large pore volume (~1.19 cm(3)/g), and uniform bimodal mesopore size (<2.0 and 4.0 nm). The monodispersed gold nanoparticles are highly exposed because of the interpenetrated bimodal pores in the carbon framework, which exhibit excellent catalytic performance. A completely selective conversion of benzyl alcohol in water to benzoic acid can be achieved at 90 °C and 1 MPa oxygen. Benzyl alcohol can also be quantitatively converted to benzoic acid at 60 °C even under an atmospheric pressure, showing great advantages in green chemistry. The catalysts are stable, poison resistant, and reusable with little activity loss due to metal leaching. The silane coupling agent played several functions in this approach: (1) coordinating with gold species by the thiol group to benefit formation of monodispersed Au nanoparticles; (2) reacting with phenolic resins by silanol groups to form relatively "rigid" composite framework; (3) pore-forming agent to generate secondary pores in carbon pore walls, which lead to higher surface area, larger pore volumes, and higher accessibility to to the gold nanoparticles. Complete removal of the silica component proves to have little effect on the catalytic performance of entrapped Au nanoparticles.

Supporting InformationFigure S1. NH 3 temperature-programmed desorption profiles for LTA zeolite samples: Na +ionic form of bulk zeolite (NaA-0), Na + -ionic form of mesoporous zeolite (NaA-2), Ca 2+ionic form of bulk zeolite (CaA-0), and Ca 2+ -ionic form of mesoporous zeolite (CaA-2). The CaA samples exhibit ammonia desorption at high temperature as compared to NaA, which indicates that the CaA samples have stronger acid sites. The mesoporous CaA-2 zeolite exhibits only a slight decrease of desorption peak intensity at high temperature as compared to CaA-0, which is not sufficient to support the large selectivity difference in the methanol conversion reaction. For the desorption measurement, 50 mg powder sample was introduced into a quartz reactor and degassed under vacuum at 823 K. After cooling to room temperature, NH 3 gas was adsorbed for 1 h, which was followed by evacuation at 383 K for removing free and weakly adsorbed NH 3 . Desorption profile was then measured with evacuation at the temperature gradient of 10 K min -1 , using a thermal conductivity detector.