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Zeolite nanosheets with excellent mass transfer are attractive, but their successful syntheses are normally resulted from a huge number of experiments. Here, we show the design of a small organic template for the synthesis of self-pillared pentasil (SPP) zeolite nanosheets from theoretical calculations in interaction energies between organic templates and pentasil zeolite skeletons. As expected, the SPP zeolite nanosheets with the thickness at 10-20 nm have been synthesized successfully. Characterizations show that the SPP zeolite nanosheets with about 90% MFI and 10% MEL structures have good crystallinity, the house-of-card morphology, large surface area, and fully four-coordinated aluminum species. More importantly, methanol-to-propylene tests show that the SPP zeolite nanosheets exhibit much higher propylene selectivity and longer reaction lifetime than conventional ZSM-5 zeolite. These results offer a good opportunity to develop highly efficient zeolite catalysts in the future.

An organotemplate-free synthesis of Al-rich ZSM-35 (Si/Al ratio at about 5) and ZSM-22 (Si/Al ratio at about 20) zeolites has been successfully shown with the addition of ZSM-57 zeolite seeds in the absence of organic templates.

The metal-exchanged zeolites as catalysts have been widely applied in many catalytic reactions, but their syntheses are environmentally unfriendly due to the multiple steps such as ion-exchange for the formation of a large amount of wastes. Herein, we for the first time report a method for one-pot fabrication of metal-zeolite catalysts (M-SSZ-13, M-Beta, M-ZSM-5, and M-EU-1; M = Cu, Co, Ni) from a combination of solvent-free and sodium-free routes by mixing, grinding, and heating the raw materials of aluminosilicate gel, organic templates, and metal-amine complexes. As a typical example, Cu-SSZ-13 zeolite is successfully synthesized from heating the mixture of aluminosilicate gel, organic template, and Cu-amine complex. Catalytic tests in selective catalytic reduction of NOx with NH3 (NH3-SCR) show that the synthesized Cu-SSZ-13 zeolite before and after hydrothermal aging at 750 °C for 16 h are completely comparable with the commercial Cu-SSZ-13 zeolite from the conventional hydrothermal synthesis. Very interestingly, the method in this work has obvious advantages such as high yield, reduced pollutants, and simple process, which should be potentially important for practical applications of the metal-zeolites in the future.

Ionothermal synthesis has been widely used for the preparation of aluminophosphate-based molecular sieves, coordination polymers, metal-organic frameworks, and covalent organic frameworks. However, this method is still challenging for synthesis of silica-based zeolites. Herein, we show a generalized ionothermal route to synthesize silica-based zeolites with MTT, TON, ITW, and MFI structures in the presence of NH4F as a mineralizing agent and ionic liquid as a solvent and/or structure directing agent. The presence of a suitable amount of NH4F plays a key role for the successful synthesis of these silica-based zeolites. This methodology might open a pathway to ionthermally synthesize silica-based zeolites.

Currently, the synthesis of pure silica zeolites always requires the presence of organic structure-directing agents (OSDAs), which direct the assembly pathway and ultimately fill the pore space. A sustainable route is now reported for synthesizing pure silica zeolites in the absence of OSDAs from a combined strategy of zeolite seeding and alcohol filling, where the zeolite seeds direct crystallization of zeolite crystals from amorphous silica, while the alcohol is served as pore filling in the zeolites. Very importantly, the alcohol could be fully washed out from zeolite pores by water at room temperature, which completely avoids calcination at high temperature for removal of OSDAs in the synthesis of pure silica zeolites.

Ultrathin nanosheets (6–8 nm) of aluminosilicate FER zeolites have been successfully synthesized using a sole small organic ammonium (N,N-diethyl-cis-2,6-dimethyl piperidinium, DMP). Catalytic tests on the skeletal isomerization of 1-butene to isobutene show that the FER nanosheets exhibit much higher conversion and selectivity than conventional FER zeolites.

2,6-methyl-N-methylpyridinium, as a novel organic template, is employed for the synthesis of RTH aluminosilicate zeolite with a SiO2/Al2O3 ratio of 17.6. The amount of 2,6-methyl-N-methylpyridinium template, the Na2O/SiO2 ratio, the SiO2/Al2O3 ratio, and the H2O/SiO2 ratio in the starting gel significantly influence the crystallization of RTH zeolite. Several analytical methods such as XRD, SEM, N2 sorption, TG-DTA, DRIFT and NMR were employed for the characterisation of the obtained RTH zeolites and to understand the crystallization process with the new template. Very interestingly, the crystallization of RTH zeolite with the new template takes a very short time (12 h at 130 °C and 50 min at 240 °C) compared with conventional RTH zeolite synthesis reported in the literature (72 h at 130 °C). Theoretical calculations show that this novel organic template has lower interaction energies for zeolite cage space filling than those of the organic templates previously reported in the literature, which lead to stronger structural directing. Kinetic results show that the activation energy of this novel organic template is much lower than that of the traditional one. Catalytic tests show that copper exchanged RTH zeolite (Cu-RTH) exhibits good catalytic properties in the NH3-SCR reaction and the H-RTH zeolite catalyst has excellent selectivities for ethylene and propylene in MTO reactions.

Development of the sustainable routes for synthesis of ITQ-family zeolites is very important because of their unique structures and excellent catalytic and adsorptive properties. The burden of costly raw materials and low efficiency of synthesis put a strong challenge for their widespread commercial application. Here, we show an alternative and simple route for synthesis of ITQ-12, ITQ-13, and ITQ-17 zeolites using commercially available organic templates by a facile grinding process of anhydrous starting raw solids, followed by heating at 140—180 °C. Compared with the conventional hydrothermal synthesis, this approach has obvious advantages such as employment of low-cost organic templates with very high effectiveness, high yield of zeolite products, short crystallization time, and relatively simple procedures. This methodology might open a pathway to synthesize ITQ zeolites with more sustainable manner.

Aluminosilicate SSZ-39 zeolite shows the excellent catalytic performance in selective catalytic reduction of NOx with NH3 (NH3-SCR) reaction, but their synthesis is still not efficient due to the use of a large amount of water as a solvent under hydrothermal condition. Herein, for the first time, we report a solvent-free synthesis of aluminosilicate SSZ-39 zeolite without addition of water in the presence of N,N-dimethyl-3,5-dimethylpiperidine (DMDMP) cation as an organic structure-directing agent. Various characterizations, including powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2 sorption, inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis, solid nuclear magnetic resonance (NMR) and NH3-temperature-programmed desorption (NH3-TPD), show that the aluminosilicate SSZ-39 zeolite displays high crystallinity, uniform sheet-like morphology, large surface area, four-coordinated aluminum species, strong acidic sites and excellent hydrothermal stability. Compared with the conventional synthesis for aluminosilicate SSZ-39 zeolite, the solvent-free synthesis of aluminosilicate SSZ-39 zeolite has the obvious advantages such as high product yield, simple synthesis procedures, and the reduction of pollutants. More importantly, the copper-exchanged aluminosilicate SSZ-39 zeolite shows the good catalytic performance in NH3-SCR reaction, which is fully comparable with that of the Cu-SSZ-39 zeolite synthesized under hydrothermal condition from the reported literature.

Structurally interlocked multi-armed carbon with a highly extended surface may be conveniently prepared by the deterministic growth of ZIF-8 on ZnO multiarms and the subsequent pyrolysis, which exhibits excellent stability and methanol corrosion resistance for oxygen reduction application.

Magnetically active, thermally stable, and ordered mesoporous resin (MOMR-200) and carbon (MOMC-200) monoliths were prepared by one-pot hydrothermal synthesis from resol, copolymer surfactant, and iron cations at high-temperature (200 ∘C), followed by calcination at 360 ∘C and carbonization at 600 ∘C. X-ray diffraction results show that both MOMR-200 and MOMC-200 have ordered hexagonal mesoporous symmetry, and N2 isotherms indicate that these samples have uniform mesopores (3.71, 3.45 nm), high surface area (328, 621 m2/g) and large pore volume (0.31, 0.43 cm3/g). Transmission electron microscopy shows that iron nanoparticles, which are superparamagnetic in nature, are dispersed in the network. More importantly, the high temperature (200 ∘C) products exhibit much better stability than the samples synthesized at low temperature (100 ∘C). Interestingly, MOMC-200 has higher adsorption capacity for organic dyes when compared with commercial adsorbents (activated carbon and macroporous resin: XAD-4). Combining the advantages such as magnetically active, thermally stable networks, ordered and open mesopores, high surface area, large pore volume, adsorption of pollutants in water and desorption in ethanol solvent, MOMC-200 is potentially important for water treatments.

Magnetically active and SO3H-functionalized ordered mesoporous resin and carbon (MOMR-SO3H, MOMC-SO3H) were successfully prepared by high-temperature hydrothermal synthesis from resol, copolymer surfactant, and iron cations at 180 °C, followed by sulfonation from sulfuric acid fuming. X-ray diffraction patterns show that MOMR-SO3H and MOMC-SO3H have ordered hexagonal mesoporous symmetry. N2 isotherms indicate that these samples have uniform and opened mesopores, high surface areas (335–591 m2/g), and large pore volumes (0.34–0.35 cm3/g). Transmission electron microscopy shows that iron nanoparticles, which are superparamagnetic in nature, are highly dispersed in MOMC-SO3H sample. Catalytic tests show that MOMC-SO3H is highly active and excellently recyclable in esterification of acetic acid with butanol, esterification of acetic acid with cyclohexanol, and condensation of benzaldehyde with ethylene glycol. More interestingly, MOMC-SO3H catalyst is magnetically active, showing potential applications for separating catalysts by a magnetic field in the future.

Small-pore zeolite levyne has been successfully synthesized following an organotemplate-free route using RUB-50 zeolite as seeds with the aid of a small amount of alcohols. Physicochemical characterization with a combination of techniques including XRD, N 2 adsorption, FE-SEM, 27 Al and 29 Si NMR, and TPD-NH 3 shows that the zeolitic product from this seed-directed organotemplate-free synthesis approach (designated as LEV-SDS) has good crystallinity, high surface area, uniform crystals, tetrahedral Al 3+ species, and abundant acidic sites. It is also found that alcohols play an important role in preparation of LEV-SDS zeolite by inhibiting the formation of MOR zeolite. Catalytic tests for the conversion of methanol-to-olefins (MTO) show that H-form of LEV-SDS zeolite exhibits good conversion of methanol and high selectivities for ethylene and propylene, which could be potentially important for using LEV-SDS zeolite as a catalyst in MTO reaction.

Novel excellent hydrophobic- mesoporous- polymer-based solid acid catalysts have been successfully synthesized by copolymerization of divinylbenzene (DVB) with sodium p-styrene sulfonate (H-PDVB-x-SO3H's) under solvothermal conditions. N2 isotherms and TEM images showed that H-PDVB-x-SO3H's have high BET surface areas, large pore volumes, and abundant mesoporosity; CHNS element analysis and acid–base titration technology showed that H-PDVB-x-SO3H's have adjustable sulfur contents (0.31–2.36 mmol/g) and acidic concentrations (0.26–1.86 mmol/g); TG curves showed that H-PDVB-x-SO3H's exhibited much higher stability of the active site (372 °C) than that of the acidic resin of Amberlyst 15 (312 °C); contact angle and water adsorption tests showed that H-PDVB-x-SO3H's exhibited excellent hydrophobic properties. Catalytic tests in esterification of acetic acid with cyclohexanol, esterification of acetic acid with 1-butanol, and condensation of benzaldehyde with ethylene glycol showed that H-PDVB-x-SO3H's were mo...

Porous polymer supported palladium catalyst for cross coupling reactions with high activity has been successfully prepared by coordination of Pd2+ species with Schiff bases functionalized porous polymer. The catalyst has been systemically investigated by a series of characterizations such as TEM, N-2 adsorption, NMR, IR, XPS, etc. TEM and N-2 isotherms show that the sample maintains the nanoporous structure after the modification and coordination. XPS results show that chemical state of palladium species in the catalyst is mainly +2. More importantly, the catalyst shows very high activities and excellent recyclability in a series of coupling reactions including Suzuki, Sonogashira, and Heck reactions. Hot filtration and poison of catalysts experiments have also been performed and the results indicate that soluble active species (mainly Pd(0) species) in-situ generated from the catalyst under the reaction conditions are the active intermediates, which would redeposit to the supporter after the reactions.

A solvent-free route is developed for synthesizing titanosilicate zeolites with good crystallinity, uniform crystals, high surface area, and tetrahedral Ti species in the framework. Catalytic tests show that S-TS-1 exhibits almost the same catalytic activity in hexane oxidation with H2O2 as that of conventional TS-1 synthesized by a hydrothermal route.

Conventional quantum dots inherently carry the risk of cytotoxicity. Considering the biomedical limitations, an amino acid and vitamin were utilized to prepare highly luminescent carbon dots. Ascorbic acid and lysine were used to synthesize water soluble carbon dots which are highly biocompatible as both reactants and essential nutrients.

Development of sustainable routes for synthesis of zeolites is very important because of wide applications of zeolites at large scale in the fields of catalysis, adsorption, and separation. Here we report a novel and generalized route for synthesis of zeolites in the presence of NH4F from grinding the anhydrous starting solid materials and heating at 140-240 °C. Accordingly, zeolites of MFI, BEA*, EUO, and TON structures have been successfully synthesized. The presence of F(-) drives the crystallization of these zeolites from amorphous phase. Compared with conventional hydrothermal synthesis, the synthesis in this work not only simplifies the synthesis process but also significantly enhances the zeolite yields. These features should be potentially of great importance for industrial production of zeolites at large scale in the future.

Mesoporous zeolites are useful solid catalysts for conversion of bulky molecules because they offer fast mass transfer along with size and shape selectivity. We report here the successful synthesis of mesoporous aluminosilicate zeolite Beta from a commercial cationic polymer that acts as a dual-function template to generate zeolitic micropores and mesopores simultaneously. This is the first demonstration of a single nonsurfactant polymer acting as such a template. Using high-resolution electron microscopy and tomography, we discovered that the resulting material (Beta-MS) has abundant and highly interconnected mesopores. More importantly, we demonstrated using a three-dimensional electron diffraction technique that each Beta-MS particle is a single crystal, whereas most previously reported mesoporous zeolites are comprised of nanosized zeolitic grains with random orientations. The use of nonsurfactant templates is essential to gaining single-crystalline mesoporous zeolites. The single-crystalline nature endows Beta-MS with better hydrothermal stability compared with surfactant-derived mesoporous zeolite Beta. Beta-MS also exhibited remarkably higher catalytic activity than did conventional zeolite Beta in acid-catalyzed reactions involving large molecules.

A novel synthetic route is designed, employing both high temperature and a nontoxic organic structure-directing agent (SDA), for the synthesis of high silica zeolite Y. The N-methylpyridinium used as an organic SDA is stable during the synthesis, and the high silica zeolite Y shows high hydrothermal stability and good catalytic performance, as well as excellent adsorptive properties.

A family of polymer-attached phenanthrolines was prepared from solvothermal copolymerization of divinylbenzene with N-(1,10-phenanthroline-5-yl)acrylamide in different ratios. The polymer-supported copper catalysts were obtained through typical impregnation with copper(II) salts. The polymers and supported copper catalysts have been characterized by N2 adsortion, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TG); they exhibit a high surface area, hierarchical porosity, large pore volume, and high thermal and chemical stabilities. The copper catalyst has proved to be highly active for Glaser homocoupling of alkynes and Huisgen 1,3-diolar cycloaddition of alkynes with benzyl azide under mild conditions at low catalyst loading. The heterogeneous copper catalyst is more active than commonly used homogeneous and nonporous polystyrene-supported copper catalysts. In particular, the catalyst is easily recovered and can be recycled at least ten times without any obvious loss in catalytic activity. Metal leaching was prevented due to the strong binding ability of phenanthroline and products were not contaminated with copper, as determined by ICP analysis.

Homogeneous catalysts usually show higher catalytic activities than heterogeneous catalysts because of their high dispersion of catalytically active sites. We demonstrate here that heterogeneous catalysts of ionic liquids functionalized on superhydrophobic mesoporous polymers exhibit much higher activities in transesterification to form biodiesel than homogeneous catalysts of the ionic liquids themselves. This phenomenon is strongly related to the unique features of high enrichment and good miscibility of the superhydrophobic mesoporous polymers for the reactants. These features should allow the design and development of a wide variety of catalysts for the conversion of organic compounds.

As important industrial materials, microporous zeolites are necessarily synthesized in the presence of solvents such as in hydrothermal, solvothermal, and ionothermal routes. We demonstrate here a simple and generalized solvent-free route for synthesizing various types of zeolites by mixing, grinding, and heating solid raw materials. Compared with conventional hydrothermal route, the avoidance of solvents in the synthesis not only significantly reduces the waste production, but also greatly increases the yield of zeolite products. In addition, the use of starting solid raw materials remarkably enhances the synthesis efficiency and reduces the use of raw materials, energy, and costs.

Low-cost copper-amine complex was rationally designed to be a novel template for one-pot synthesis of Cu-SSZ-13 zeolites. Proper confirmation and appropriate size make this complex fit well with CHA cages as an efficient template. The products exhibit superior catalytic performance on NH(3)-SCR reaction.

We have demonstrated that an organotemplate-free and seed-directed route has been successfully applied for synthesizing Fe-Beta zeolite with good crystallinity, high surface area, uniform crystals, and tetrahedral Al3+ and Fe3+ species. Catalytic tests for the direct decomposition of nitrous oxide indicate that the Fe-Beta exhibits excellent catalytic performance.

Sulfonated hollow sphere carbon (HSC-SO3H) was synthesized from carbonization of a SiO2–polymer core–shell structure, followed by removal of the SiO2 core and sulfonation with chlorosulfonic acid. HSC-SO3H shows superior performances in acetalisation of glycerol, which is related to the hollow sphere carbon shell with rich microporosity for good mass transfer in the reaction.

Plate-like micro-sized MOR and Fe-MOR zeolite crystals assembled from highly uniform nano-rods are successfully fabricated by an organotemplate-free method during one-pot crystallization in the presence of a MOR seed solution. The seed solution rich in 4-membered rings plays a critical role for the formation of the unique nano-rod assembled structure.

Graphene with its two-dimensional sheet of sp2-hybridized carbon is a hot topic in the fields of materials and chemistry due to its unique features. Herein, we demonstrate that sulfated graphene is an efficient solid catalyst for acid-catalyzed liquid reactions. The sulfated graphene was synthesized from a facile hydrothermal sulfonation of reduced graphene oxide with fuming sulfuric acid at 180 °C. Combined characterizations of XRD, Raman, and AFM techniques show that G-SO3H has a sheet structure (1–4 layers). IR spectroscopy shows that G-SO3H has a SO bond, and the XPS technique confirms the presence of an S element in G-SO3H. Acid–base titration indicates that the acidic concentration of sulfonic groups in the sulfated graphene is 1.2 mmol g−1. TG curves shows that the decomposition temperature (268 °C) of the sulfonic groups on the sulfated graphene is much higher than that of conventional SO3H-functionalized ordered mesoporous carbon (237 °C). Catalytic tests of the esterification of acetic acid with cyclohexanol, the esterification of acetic acid with 1-butanol, the Peckmann reaction of resorcinol with ethyl acetoacetate, and the hydration of propylene oxide show that sulfated graphene is much more active than the conventional solid acid catalysts of Amberlyst 15, OMC-SO3H, SO3H-functionalized ordered mesoporous silica (SBA-15-SO3H), graphene oxide, and reduced graphene oxide, which is attributed to the fact that the sulfated graphene almost has no limitation of mass transfer due to its unique sheet structure. Very importantly, the sulfated graphene has extraordinary recyclability in these reactions, which is attributed to the stable sulfonic groups on the sulfated graphene. The advantages, including high activities and good recyclability as well as simple preparation, are potentially important for industrial applications of the sulfated graphene as an efficient heterogeneous solid acid catalyst in the future.

The methanol-to-olefins (MTO) reaction over zeolites is of great importance due to the shortage of crude oil, and we demonstrate here a fast, organotemplate-free, and seed-directed synthesis of ZSM-34 zeolite, designated as ZSM-34-S, having very high selectivity for propylene. When the temperature is at 140–180 °C, ZSM-34-S zeolite could be crystallized for 2–6 h in the presence of ZSM-34 crystals as seeds. For industry, a fast and organotemplate-free synthesis, a typically green route, means significant savings in energy and costs. Characterizations using XRD, SEM, 27Al and 29Si MAS NMR, and N2 sorption techniques show that the ZSM-34-S crystals grow from the seeds of ZSM-34 crystals in an amorphous aluminosilicate. Catalytic tests of the MTO reaction show that HZSM-34-S has a very high selectivity for propylene (55.2%), which is even higher than that (47.0%) of SAPO-34 under the same conditions. Moreover, the hydrothermal treatment of HZSM-34-S significantly improves the catalyst life for MTO due to decreasing acidic concentration and increasing anti-deactivation. The combination of a “green” synthesis and the good catalytic performance of ZSM-34-S would be potentially important for the highly effective conversion of methanol, which can be easily obtained from coal, natural gas, or biomass at a large scale.

Hierarchically porous aluminophosphates (SF-APOs) and metal substituted aluminophosphates (SF-MAPOs, M = Co, Fe, Cr) have been synthesized via simple grinding and heating in the absence of solvent. Characterization results show that these mesoporous aluminophosphates have a hierarchically microporous/mesoporous structure. In addition, metal atoms can be efficiently incorporated into the walls of mesoporous aluminophosphates, and the SF-CoAPO sample shows high catalytic activity in cyclohexene oxidation compared with microporous samples. Special features of the “solvent-free” synthesis route, such as increasing product yield, saving energy, elimination of pollution, and convenience for incorporation of heterogeneous atoms, ensure its great potential in the synthesis of porous materials.

We have demonstrated here for the first time that high-silica ferrierite zeolite, designated as ZJM-2, is successfully synthesized by an induction of CDO-structure zeolite building units in the absence of organic templates. The resulting ZJM-2 has good crystallinity, high surface area, similar crystals shape, only tetrahedral Al3+ species, and abundant acidic sites.