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Super-microporous alumina (pore size between 1 and 2 nm) with polycrystalline walls and high surface area (more than 650 m 2 /g) was synthesized successfully via an evaporation induced self-assembly (EISA) pathway using readily available and inexpensive nonionic surfactant fatty alcohol polyoxyethylene ether (AEO-7) as the template. N 2 adsorption-desorption results showed that the obtained materials are super-microporous when removing the template at 400 °C, then if the calcination temperature increase from 600 °C to 1000 °C, a breakdown of the walls separating adjacent pores allows the transformation to mesopores (pore size > 2 nm). FTIR pyridine adsorption and NH 3 -TPD measurement suggested the presence of strong Lewis acid sites. Transmission electron microscopy (TEM) measurements indicated that the alumina possesses the disordered “wormhole-like” super-microporous structure with polycrystalline walls. Loaded with copper, the catalyst exhibited outstanding activity in the selective catalytic reduction of NO with methane and could achieve a NO x conversion 100% when the reaction temperature is over 600 °C. [ABSTRACT FROM AUTHOR]

• A hierarchical zeolite Beta with self-assembled morphology of nanosized crystallines. • Nanosized crystallites aggregated by10–50 nm result from addition of GO. • Admirable connectivity of mesopores in the zeolite materials. • High hierarchical factor with high external surface area and mesoporous volume. Hierarchical zeolite Beta has been successfully synthesized by adding graphene oxide (GO) in the hydrothermal system and characterized by XRD, SEM and N 2 adsorption-desorption. The results show that the mesoporous distribution of the hierarchical zeolite Beta can be adjusted in the range of 3–7 nm and the mesoporosity can be varied by changing the type and content of GO. The formation of mesoporous structure in the zeolitic particles is from that the growth of crystalline is blocked in part by GO attached onto the zeolitic crystalline surface. Compared to spherical structure of GO nanopowders, laminar structure of GO nanosheets is propitious to increase the connectivity of the mesopores in the zeolite materials. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Micro-mesoporous alumina-zirconia nanocrystals are prepared by vapor-induced route. • The Al incorporation improves the textural properties of the composites. • The largest surface area of 313 m2/g is obtained. • The samples possess stable tetragonal structure of zirconia. • The samples show large pore volumes in the range of 0.18–0.39 cm3/g. Abstract Micro-mesoporous alumina-zirconia nanocrystals with controllable textural properties are prepared using triblock copolymer F127 as a template via one-pot vapor-induced pathway. The BET surface area and pore volume of the samples increase with rising aluminum content. When the Al/Zr molar ratio is 0.6, the sample exhibits highest surface area of 313 m2/g of which 118 m2/g in the form of micropores after high temperature calcination. Moreover, the incorporation of Al species enhances the structural stability of zirconia in tetragonal phase. [ABSTRACT FROM AUTHOR]

Super-microporous nanocrystalline zirconia (pore size 1–2 nm) was synthesized via the evaporation-induced self assembly (EISA) process with solid–liquid method. The acidic etching process of zirconia resulted in the formation of microporous material with surface area of 414 m 2 /g in comparison with that of 141 m 2 /g for the parent material when treated at 400 °C. Even after calcination at 700 °C, the pore structure was fairly preserved for the post-treated samples and the material still exhibited a high surface area of 223 m 2 /g. However, for samples without post-treatment, their pore walls collapsed totally and surface area decreased drastically when calcinated at 550 °C. [ABSTRACT FROM AUTHOR]

In order to immobilize neutral or positive metal complexes on layered double hydroxides (LDHs) and increase the amount of immobilized metal complexes, a novel strategy for the preparation of metal complex functionalized LDHs is proposed. This strategy involves exfoliating glycine-intercalated MgAl LDH in formamide under an ultrasound treatment, and then grafting silylated metal complexes on MgAl LDH nanosheets, as exemplified by immobilization of Co Schiff-base on MgAl LDHs. The prepared hybrids were characterized by XRD, AFM, FT-IR, TG, N 2 adsorption–desorption and ICP techniques and their catalytic performances were investigated in H 2 O 2 decomposition and styrene epoxidation with O 2 . The results showed that the hybrid prepared by this strategy had higher Co Schiff-base loading than the sample prepared by directly grafting silylated Co Schiff-base on glycine-intercalated MgAl LDHs due to the more accessible grafting sites on the exfoliated MgAl LDH nanosheets. Additionally, it was found that the grafted complexes could effectively impede the restack of LDH nanosheets after removal of the solvent. Thus, the prepared hybrid exhibited higher surface area and more accessible active centers, which made the prepared hybrid exhibit high catalytic activity in H 2 O 2 decomposition and styrene epoxidation with O 2 . This work gives us a new way to prepare LDH hybrids functionalized with various metal complexes. [ABSTRACT FROM AUTHOR]

A series of hierarchical SAPO-34 zeolites with controllable crystallite sizes ranging from 40 to 200 nm and morphologies from well-dispered urtral-small nanocrystals to compact spherical-like polycrystallite aggregates were fabricated by only modulating the Si/TEAOH molar ratios in the gel mixture. [Display omitted] • Hierarchical SAPO-34 zeolites are synthesized without a secondary template. • A possible forming mechanism of SAPO-34 zeolite is proposed. • Crystal sizes and morphologies can be well modulated by controlling Si/TEAOH molar ratios. • The rich mesopore structure resulted from the intercrystal pores of nanoparticles is fabricated. A series of hierarchically porous SAPO-34 zeolites with tunable crystal sizes varying from 40 to 200 nm were synthesized with different morphologies from well-dispersed ultra-small nanocrystals to compact spherical-like polycrystalline aggregates by only changing the Si/TEAOH (TEAOH: tetraethylammonium hydroxide) molar ratios in the gel precursors without using any meso -templates. The hierarchical samples were systematically characterized by XRD, FT-IR, SEM, TEM, XRF, 29Si MAS NMR spectra and N 2 adsorption–desorption. It reveals that hierarchical SAPO-34 nanocrystals with high crystallinities, larger external surface areas (61 – 125 m2/g) and mesopore volumes (0.15 – 0.29 cm3/g) were obtained under current synthesis condition. [ABSTRACT FROM AUTHOR]

Abstract: Y-Beta zeolite composites denoted as HS-FBZ (High-Silica-Faujasite-Beta-Zeolite) were synthesized hydrothermally using high silica Y as precursor and characterized by XRD, N2 adsorption, SEM, HRTEM, NH3-TPD and FT-IR spectra of pyridine. The results reveal that the different ratios of Y and Beta zeolites in the composites induced the change of surface areas, pore diameters and acid properties of HS-FBZ, and the extended Beta layers on the zeolite Y surface were observed. The composite exhibited an excellent hydrocracking activity for heavy oil. Compared with the corresponding physical mixture of Y and Beta zeolites, the zeolite composite as a hydrocracking catalyst for vacuum gas oil increased the heavy naphtha yield by 5.61wt% and the jet fuel yield by 11.52wt%. [Copyright &y& Elsevier]

Flowerlike hierarchical SAPO-5 molecular sieve with affluent mesopores derived from loosely aggregating of primary nano-rods-like crystals is prepared via a hydrothermally rota-crystallization route using tetrapropylammonium hydroxide as a single structure-directing agent. • Flowerlike SAPO-5 molecular sieve is synthesized by a hydrothermally rota-crystallization route. • Flowerlike SAPO-5 is composed of loosely aggregating rod-like crystals with a size of ~20 nm. • Mesopore of 2–8 nm resulted from the intercrystalline spaces is fabricated. Flowerlike hierarchical SAPO-5 molecular sieve was fabricated by a hydrothermally dynamic crystallization route using tetrapropyl-ammoniuhydroxide as a single structure-directing agent. The hierarchical SAPO-5 reveals high crystallinity, and large external surface areas validated by the XRD and N 2 adsorption-desorption. SEM and TEM indicate that the flowerlike hierarchical SAPO-5 is composed of loosely stacked primary nanorods with average diameter of 20 nm. FT-IR and EDS analyses show that as increasing crystallization time, more and more Si species are incorporated into the AFI crystals. Moreover, it is found that a dynamic crystallization condition is very mandatory toward the synthesis of a novel-flowerlike SAPO-5. [ABSTRACT FROM AUTHOR]

• Well-crystallized zeolite Y assembled by nanocrystals with intercrystal mesopores. • The nanocrystal zeolite Y lying on both gel formation and aging at low temperature. • Presence of CTAB improving the assemblies of zeolite Y nanocrystals. • Highly active accessibility and rapid diffusion in the zeolite Y to bulk molecules. Zeolite Y nanocrystal assembly was synthesized by using cetyltrimethyl ammonium bromide (CTAB) under low gelling and aging temperature in the hydrothermal system. XRD, SEM, N 2 adsorption/desorption isotherms, 29Si and 27Al MAS NMR spectra as well as NH 3 -TPD demonstrated that the synthesized zeolite Y is a mesoporous zeolite composed of well-developed nanocrystals with high external surface area, intercrystal mesoporosity and acidity. The conversions of 1,3,5-trimethylbenzene (TMB) and 1,3,5-triisopropylbenzene (TIPB) reflect its superior features for isomerization, selectivity of bulky molecule and catalytic stability. [ABSTRACT FROM AUTHOR]