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The influence of synthesis parameters (e.g. Si/Al ratio, pH of the reaction mixture, structure of Gemini-type surfactant) on the phase selectivity of nanocrystalline MOR formation was studied. The nature of organic structure-directing cation (i.e. charge, size) was found as a decisive factor controlling morphology of MOR nanocrystals. Fabricated nanocrystalline MOR zeolites showed enhanced textural characteristics (BET area, total pore volume) and higher catalytic activity (TOF = 42–45 vs. 15 h−1) in acid-catalyzed annulation reaction of 2-naphtol with methylbut-3-en-2-ol when compared to commercial microcrystalline MOR zeolite.

Hydrogen adsorption over silicon carbide of different nature was investigated. High specific hydrogen adsorption (up to 15 μmol/m2), nontypical for silicon carbide was obtained for the materials prepared by the template method. A more perfect truly "carbide" structure (with a higher content of Si–C bonds in the form of carbide) in this type of materials contributes to an increase of the specific hydrogen adsorption. However, some non-stoichiometricity manifested in the presence of carbon in other (non-carbide) bonds (graphite or terminal and sp3 hybridized C) is required for exceptionally high specific hydrogen adsorption. The influence of the adsorbate nature for several gases (Н2, N2, CO) was found to be less prominent for SiC compared to carbon and silica materials. This feature inherent only to silicon carbide exhibiting an increased level of specific hydrogen adsorption, is due to cooperative adsorption, accompanied by an abnormally high loading of the adsorbent surface in the supercritical region.

Samples of porous silicon carbide were obtained using sucrose or carbon and aerosil or silica mesoporous molecular sieves (SBA-3, SBA-15, KIT-6 and MCF). Fibers content in silicon carbide samples is higher when the mesopore surface area of carbon materials derived from carbon-silica composites is lower. Based on the found correlation between the morphology and porosity of SiC and mesopore surface area of the carbon component in the composites, a templating action of carbon in carbothermal reduction was suggested.

Partly zeolitized micro-mesoporous aluminosilicates SBA-15/ZSM-5 were synthesized by conversion of dry gel of template-containing SBA-15 in the presence of tetrapropylammonium hydroxide. They have a hexagonally ordered mesostructure and developed surface and mesoporosity for which the concentration and strength of the Bronsted and Lewis acid sites are higher than in AlSi-SBA-15. The formation of Bronsted acid sites of moderate strength in the samples with a low degree of zeolitization is due to the presence of ZSM-5 precursors as well as crystallites in the obtained aluminosilicates.

Heat treatment of carbon–silica composites derived from micro-mesoporous zeolite-like materials yields the β-modification of silicon carbide with adsorption characteristics much superior to those of analogs obtained using large-porous silica exotemplates (meso-cellular foams). The presence of a large volume of relatively homogeneous mesopores, which permits us to achieve a close-to-stoichiometric C/SiO2 ratio, accounts for the formation of silica carbide with well-developed porosity.

Micro-mesoporous aluminosilicates consisting of agglomerates of the ZSM-5 nanoparticles were obtained using dual-functional templates [C6H13–N+(CH3)2–C6H12–N+(CH3)2–C6H13](Br−)2 (C6–6–6Br2), [C8H17–N+(CH3)2–C6H12–N+(CH3)2–C8H17](Br−)2 (C8–6–8Br2). Aluminosilicates with randomly oriented flake-like particles built from ZSM-5 layers were obtained using [C16H33–N+(CH3)2–C6H12–N+(CH3)2–C6H13](Br−)2 (C16–6–6Br2). Use of С8–6–8Br2 and additive of cetyltrimethylammonium bromide CTAB (CTAB concentration is lower than the first critical micelle concentration, CMC1) leads to an increase of the total specific surface area, mesopore surface area and the mesopore size uniformity in the product, as well as the concentration of Bronsted acid sites accessible for bulk molecules. It is assumed that CTAB role is to limit the zeolite crystals growth. Addition of CTAB to С16–6–6Br2 (CTAB concentration is also lower than CMC1) promotes the formation of micro-mesoporous aluminosilicate possessing disordered lamellar mesostructure stable upon calcination which is characterized by a higher total specific surface area and better mesopores uniformity than ZSM-5 obtained in the presence of С16–6–6Br2. The additive of a molecular template tetrapropylammonium hydroxide (TPAOH) shifts the structure formation toward zeolite and leads to an increase in the ratio of concentrations of Bronsted and Lewis acid sites for the obtained aluminosilicates. The addition of small amounts of TPAOH into the reaction mixture (TPAOH/C16–6–6Br2 = 6.5·10−3) leads to formation of self-pillared aluminosilicate. In this material the nanoparticles act as “pillars” between the layers of ZSM-5 and thus contribute to retention of low-ordered lamellar mesostructure after calcination, leading to increase of the total specific surface area and improving mesopores uniformity.

Samples of crystal modifications of porous silicon carbide were obtained by carbothermal method using carbon precursors (sucrose, carbon) and aerosil or mesoporous silicas molecular sieves SBA-3, SBA-15, KIT-6, and MCF as silicon sources. Porous β-SiC samples obtained from carbon–silica composites are characterized by high structural and sorption characteristics (S BET up to 410 m2/g, V pore up to 1.0 cm3/g). High hydrogen adsorption capacity of silicon carbide samples based on KIT-6 (up to 1.24 wt% at 77 K and 1 atm.), considering low adsorption energy ( $$ \left| {\Delta \mu_{0} } \right|_{{{\text{H}}_{2} }} $$ ) up to 2.3 kJ/mol for SiC vs. ca. 5.0 kJ/mol for carbon), was determined. The highest ever reported value among the existing porous materials was observed for specific adsorption of H2 by SiC (specific adsorption on the pore surface, ρ up to 15 μmol/m2) corresponding to almost complete filling of the surface with hydrogen in the examined conditions (77 K, 1 atm.).

Boron-doped carbon nanostructures were obtained via template and bulk synthesis from sucrose in the presence of boric acid. Synthesized B-containing mesoporous materials are characterized by high spatial ordering, developed surface (up to 870 m2/g), and porosity (up to 1.2 cm3/g). The obtained B-doped microporous materials exhibit high interfacial capacitance (up to 0.36 F/m2), which is higher than the available literature data and enables the use of synthesized samples as materials of supercapacitors. The capacity of electric double layer up to 300 F/g using sulfuric acid as the electrolyte was accumulated on microporous B-doped carbons.

Micro-mesoporous alumosilicates derived from zeolite ZSM-5 were obtained in dual template reaction media and in the presence of dual functional templates. It was shown that aluminosilicates with 0.15-0.25 zeolitization exhibit high catalytic activity in cumene cracking, approaching the activity of ZSM-5 and superior to ZSM-5 in total selectivity relative to the major products (propylene and benzene). Greater oligomerization of propylene is observed with increasing micropore volume and concentration of strong acid sites in the alumosilicates along with increased cumene conversion.

Carrying out the dual template synthesis (in the presence of molecular and micellar templates) in the alkali metal-free reaction media (pH 11.7–12) at a relatively low-temperature hydrothermal treatment (100–120 °C, duration 3–5 days) allowed to obtain micro-mesoporous aluminosilicates combining the properties of zeolite ZSM-5 and mesoporous molecular sieve AlSi-MCM-41. X-ray amorphous sol-precursors of ZSM-5 zeolite obtained by preliminary hydrothermal treatment of alkali metal-free reaction mixture at 160 °C and containing secondary building units of zeolite were used as initial substances for synthesis of micro-mesoporous aluminosilicates. During the joint formation of the structure of zeolite and mesoporous molecular sieve in one reaction mixture and in contiguous conditions close to optimal for their individual formation, composites zeolite/mesoporous molecular sieve were formed. The structural and sorption characteristics and acidity of the obtained composites differ from mechanical mixture of two phases. X-ray amorphous micro-mesoporous aluminosilicate with secondary building units and precursors of ZSM-5 in mesostructure is characterized by higher concentration and strength of Bronsted and Lewis acid sites as well as a higher catalytic activity in the reaction of cracking of cumene compared to AlSi-MCM-41 of similar composition. This aluminosilicate also exhibits a higher total selectivity toward the major products of reaction, in comparison with ZSM-5.

The samples of nonstoichiometric carbon nitride characterized by spatial ordering, large pore volume (up to 0.8 cm3/g) and specific surface area (up to 585 m2/g) were obtained via matrix carbonization of ethylenediamine in the presence of carbon tetrachloride in mesoporous molecular sieves KIT-6 and MCF as exotemplates. In contrast to nitrogen-containing carbons (obtained by modification of carbon samples with nitrogen in the result of compatible thermal treatment of the initial porous carbon with melamine) nonstoichiometric carbon nitride contains much more nitrogen (up to 13.7 wt.% (C/N = 6), compared with preceding 0.6 wt.%) and increased the quantity of basic nitrogen-containing groups (in particular, amino groups)—up to 0.68 mmol/g (vs. 0.46 mmol/g). The increase of adsorption capacity towards hydrogen and carbon dioxide: adsorption potential, differential heat of CO2 adsorption, specific adsorption on the pore surface—from 5.4 to 7.3 μmol H2/m2 and from 2.2 to 5.4 μmol CO2/m2 for carbon and synthesized samples of nonstoichiometric carbon nitride, respectively, due to the incorporation of nitrogen atoms into the carbon framework was noticed.

The aim of this study was to determine the influence of the conditions of low-temperature sequential dual template synthesis of micro-mesoporous aluminosilicates based on precursors of ZSM-5 on their phase composition, structure, sorption properties, and acidity. The methods of X-ray powder diffraction and volumetric adsorption (N2, 77 K) analysis, dynamic light scattering (for characterization of sol-precursors), IR-spectroscopy, energy-dispersive X-ray spectroscopy, scanning and transmission electron microscopy, solid-state 29Si MAS NMR and 29Si{1H} cross-polarization MAS NMR spectroscopy, temperature-programmed desorption of ammonia, ad(de)sorption of pyridine and 2,6-di-tert-butylpyridine with IR-spectral control were used for characterization of the obtained micro-mesoporous aluminosilicates. It was shown that the convergence of compositions of the reaction mixtures and conditions of formation of zeolites and mesoporous molecular sieves, in particular, the use of alkali-free reaction medium and relatively low temperature of hydrothermal treatment (100 °C) allowed to obtain the X-ray amorphous and partially zeolitized micro-mesoporous aluminosilicates. Such aluminosilicates have appropriate structural and sorption properties and the acidity inherent to ZSM-5 and MCM-41, including the Bronsted and Lewis acid sites which are accessible for bulk molecules of organic substances. The possibility of purposeful regulation of characteristics of micro-mesoporous aluminosilicates depending on the conditions of their preparation was confirmed. Herewith the investigated aluminosilicates possess the sorption and acidic properties which are different from the mechanical mixture of two phases.

High structure-directing activity and specificity of templating action of tetrapropylammonium cations TPA+ as well as high concentration of framework-forming substances in the initial reaction mixtures contribute to the formation of zeolite ZSM-5 at relatively low temperature (100 °C) in the alkali-free media. Zeolite ZSM-5 obtained at 100 °C has higher micropore and mesopore volumes, specific surface area, less uniform micropore size distribution in comparison with ZSM-5 synthesized at 170 °C in an alkaline medium in the presence of hydrated Na+ cations. Samples synthesized at 100 °C possess a lower concentration of acid sites and broader distribution of them in strength, compared with ZSM-5 obtained at 170 °C in an alkaline medium. ZSM-5 obtained at 100 °C exhibits a high catalytic activity in the reaction of cracking of cumene, as well as a higher selectivity to propylene and styrene, in comparison with isostructural analogue obtained at 170 °C in an alkaline medium. It is assumed that the investigated alkali-free reaction mixtures and the corresponding sol-precursors of zeolite ZSM-5 containing the elements of secondary building units can be used for obtaining of micro-mesoporous aluminosilicates in the conditions of low-temperature synthesis (100 °C) by dual-template method—in the presence of molecular and micellar templates.

The characteristics of the dehydration, thermal desorption and thermal decomposition of organic templates in zeolite-like aluminophosphates and silica aluminophosphates of different structural types have been elucidated. The influence of the pore size and acidic centres on the composition of the thermal decomposition products, including the secondary syntheses of normal, cyclic and aromatic hydrocarbons, has been established. The possibility of dehydration, oligomerization, cyclization, cracking, aromatization and alkylation of hydrocarbons in zeolite-like phosphates has been shown.