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Generation of hierarchical zeolites is an effective way to enhance their diffusion-dependent catalytic properties. The fabrication of hierarchical zeolites with enhanced diffusion property, high hydrothermal stability, strong acidity in an inexpensive, facile and efficient way is particularly daunting. Here, a simple synthesis of hierarchical SSZ-13 zeolite in a biphasic water/toluene media under tumbling assisted by organosilane, i.e., trimethoxy[3-(phenylamino)propyl]silane, is proposed. The obtained material with tunable Si/Al from 10 to 30 consists of assembled crystallites of 20–30 nm that construct a hierarchical architecture with mesopores of ca. 7 nm opening to the external facets, and has low defect concentration and preserved strong acidity. Crystallization mechanism is disclosed to obey a non-classic attachment growth of nano building blocks mediated by Pickering emulsion, as organosilane modification changes their surface to be hydrophobic. Such a crystallization pathway has accelerated nucleation process and suppressed the growth of SSZ-13 crystals to micron size. Cu exchanged hierarchical SSZ-13 outperforms the standard sample in typical NH3-SCR process in both low and high temperature regimes as a result of enhanced diffusion property, as well as low defect concentrations. The synthesis is a cost-effective method for the generation of hierarchical zeolites mediated by the presence of a liquid/liquid interface, and could inspire more such explorations.

Understanding silicoaluminophosphate formation mechanism lays the foundation for their structure manipulation via crystallization process control. Crystallization of SAPO-34 from a dry gel using tetraethyl ammonium hydroxide as structure-directing agent was monitored to unravel the formation mechanism. The initial gel was found to form a lamellar precursor first, which subsequently underwent phase transformation to discrete SAPO-34 nanocrystallites. The nanocrystallites thereafter mutually aligned with neighboring ones via a non-classic oriented attachment growth mechanism, affording large crystals as a result of grain boundary elimination. A new protocol to prepare hierarchical SAPO-34 was designed by hindering the aggregation of primary nanocrystallites with a growth inhibitor 1,2,3-hexanetriol. The structure of hierarchical SAPO-34 was characterized by XRD, N 2 physisorption, mercury intrusion, SEM, TEM, as well as 27 Al, 29 Si, 31 P MAS NMR spectra and compared with a conventional SAPO-34. More Si islands were formed via combined SM3 (Al+P pairs substitution by 2Si) and SM2 (P substitution by Si) mechanism for hierarchical SAPO-34 as Si was not fully incorporated into the precursor lamellar phase. NH 3 -TPD showed that hierarchical SAPO-34 has comparable acidic strength to conventional SAPO-34. The obtained hierarchical SAPO-34 is comprised of

We report the synthesis and characterization of a series of new mesoporous zeolite and zeotype materials made available by combining new and improved procedures for directly introducing carbon into reaction mixtures with the fluoride route for conventional zeolite synthesis. The mesoporous materials were all prepared by hydrothermal crystallization of gels adsorbed on carbon matrices which were subsequently removed by combustion. The procedures presented here resulted in mesoporous zeolite and zeotypes materials with MFI, MEL, BEA, AFI and CHA framework structures. All samples were characterized by XRPD, SEM, TEM and N2 physisorption measurements. For the zeolite materials it was found that mesoporous MFI and MEL structured single crystals could indeed be crystallized from fluoride media using an improved carbon-templating approach. More importantly, it was found that mesoporous BEA-type single crystals could be crystallized from fluoride media by a newly developed procedure presented here. Thus, we here present the only known route to mesoporous BEA-type single crystals, since crystallization of this framework structure from basic media is known to give only nanosized crystals as opposed to mesoporous single crystals. For the zeotype materials it was found that highly crystalline mesoporous materials of AFI and CHA structure types could be synthesized using a newly developed procedure.

Imidazole type ionic liquid 1-hexadecyl-3-methylimidazolium chloride and 1-hexadecyl-3-methylimidazolium ruthenium hexachloride were used to fabricate the well-ordered hexagonal mesoporous silica (under acidic and basic conditions), and Ru–SiO 2 , respectively. Small angle X-ray diffraction, scanning electron microscopy, transmission electron microscopy and N 2 adsorption–desorption were employed to characterize the structure. The mesoporosity of the silica matrix is preserved after calcination of organic templates. The pore diameter of silica prepared from acidic media (2.20 nm) was smaller and less ordered than that of silica from basic solution (2.74 nm). Further, the mesoporous structure of Ru–SiO 2 was found to be preserved after calcination, however, RuO 2 nanoparticles formed in the matrix of mesoporous silica upon calcination.

Thermally stable mesoporous tetragonal zirconia with high surface area (153 m2/g at 700 °C) has been prepared by using bifunctional ethylene diamine as both precipitating agent for ZrOCl2 to ZrO(OH)2 and colloidal protecting agent for the ZrO(OH)2 nanoparticles. The zirconia sample was found to possess the tetragonal crystal phase exclusively. This approach avoids traditional bases such as NH3, NaOH and expensive surfactants and copolymers, which are usually employed as templates for the synthesis of high surface area and thermally stable metal oxides. Pt nanoclusters of size ∼20–30 A have been prepared in a single step chemical reduction method in aqueous media. The Pt nanoclusters have been deposited on mesoporous (pore size ≈ 35–45 A) hydrous zirconia by adopting the ‘precursor’ route. The Pt nanoclusters have been found almost evenly dispersed in the hydrous zirconia matrix without aggregation. The ethylene diamine likely serves as a link between the support (ZrO(OH)2) and Pt nanoclusters. The Pt/ZrO2 catalyst has been found to be highly active for 1-hexene hydrogenation reactions with a turnover frequency of about 20,000 h−1. All systems have been characterized by TEM, EDX, SEM, X-ray diffraction, N2 adsorption–desorption isotherms and TGA.