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The ability to control the function and structure of some promising nanosystems using an external stimulus is attractive research to develop programmable and reconfigurable intelligent nanomaterials. The focal point of this review is the silicon-based nanoporous materials, and particularly the mesoporous silica materials (MSMs) class (pore size: 2–50 nm), due to their important intrinsic properties, such as high surface area, highly ordered nanostructure, narrow pore size distribution, various dimensions (one-dimensional, two-dimensional, and three-dimensional), and easily functionable. One of the most essential organic components that can be incorporated in MSMs is organic photochromic molecules (OPMs), such as azobenzene, stilbene, dithienylethenes, and spiropyrans. OPMs can be incorporated into MSMs, to form photochromic mesoporous organosilica materials (PMOMs), in two different ways: physical (non-covalent immobilization) or chemical (covalent immobilization) binding. PMOMs are considered smart nanomaterials because they have the ability to undergo reversible changes in the solid state when exposed to an external electromagnetic radiation. PMOMs have been the subject of many research studies during the last decade due to their potential applications, especially as chemosensors. This review discusses the main families of OPMs, their incorporation into MSMs using different methods, and the applications of some PMOMs as chemosensors.

Abstract Robust solid-core silica particles with submicrometer size and anthracene-containing mesoporous shell were obtained and studied as model water-dispersable photoreactors. An anthracene derivative containing a triethoxysilyl group was synthesized and co-condensed with tetraethoxysilane in various ratios to form a photoactive mesoporous shell with a thickness up to approximately 80 nm on previously prepared solid silica particles. Mesopores of as-synthesized particles, without a commonly applied removal of the micellar templates, offered a confined space for solubilization of hydrophobic molecules. Efficient excitation energy transfer from anthracene chromophores to both hydrophobic (perylene) and hydrophilic (fluoresceine) encapsulated acceptors was observed in an aqueous dispersion of the particles. Photosensitized oxidation of encapsulated perylene was shown to proceed efficiently in such systems serving as water-dispersable photoreactors. Importantly, the designed core–shell systems were found to be stable for a long time (at least 24 months) and robust enough, thanks to the presence of solid cores, to be handled by centrifugation in aqueous dispersions. All these features make them promising candidates for reusable systems for the photosensitized degradation of water pollutants, especially hydrophobic pollutants.

Robust solid-core silica particles with submicrometer size and anthracene-containing mesoporous shell were obtained and studied as model water-dispersable photoreactors. An anthracene derivative containing a triethoxysilyl group was synthesized and co-condensed with tetraethoxysilane in various ratios to form a photoactive mesoporous shell with a thickness up to approximately 80 nm on previously prepared solid silica particles. Mesopores of as-synthesized particles, without a commonly applied removal of the micellar templates, offered a confined space for solubilization of hydrophobic molecules. Efficient excitation energy transfer from anthracene chromophores to both hydrophobic (perylene) and hydrophilic (fluoresceine) encapsulated acceptors was observed in an aqueous dispersion of the particles. Photosensitized oxidation of encapsulated perylene was shown to proceed efficiently in such systems serving as water-dispersable photoreactors. Importantly, the designed core–shell systems were found to be stable for a long time (at least 24 months) and robust enough, thanks to the presence of solid cores, to be handled by centrifugation in aqueous dispersions. All these features make them promising candidates for reusable systems for the photosensitized degradation of water pollutants, especially hydrophobic pollutants. [ABSTRACT FROM AUTHOR]

Co-condensation of mixed SiGe nanoclusters and impingement of SiGe nanoclusters on a Si substrate were applied using molecular dynamics (MD) simulation in this study to mimic the fast epitaxial growth of SiGe/Si heterostructures under mesoplasma chemical vapor deposition (CVD) conditions. The condensation dynamics and properties of the SiGe nanoclusters during the simulations were investigated first, and then the impingement of transient SiGe nanoclusters on both Si smooth and trench substrate surfaces under varying conditions was studied theoretically. The results show that the mixed nanoclusters as precursors demonstrate potential for enhancing epitaxial SiGe film growth at a high growth rate, owing to their loosely bound atomic structures and high mobility on the substrate surface. By varying cluster sizes and substrate temperatures, this study also reveals that smaller clusters and higher substrate temperatures contribute to faster structural ordering and smoother surface morphologies. Furthermore, the formed layers display a consistent SiGe composition, closely aligning with nominal values, and the cluster-assisted deposition method achieves the epitaxial bridging of heterostructures during cluster impingement, highlighting its additional distinctive characteristics. The implications of this work make it clear that the mechanism of fast alloyed epitaxial film growth by cluster-assisted mesoplasma CVD is critical for extending it as a versatile platform for synthesizing various epitaxial films. [ABSTRACT FROM AUTHOR]

Co-condensation of mixed SiGe nanoclusters and impingement of SiGe nanoclusters on a Si substrate were applied using molecular dynamics (MD) simulation in this study to mimic the fast epitaxial growth of SiGe/Si heterostructures under mesoplasma chemical vapor deposition (CVD) conditions. The condensation dynamics and properties of the SiGe nanoclusters during the simulations were investigated first, and then the impingement of transient SiGe nanoclusters on both Si smooth and trench substrate surfaces under varying conditions was studied theoretically. The results show that the mixed nanoclusters as precursors demonstrate potential for enhancing epitaxial SiGe film growth at a high growth rate, owing to their loosely bound atomic structures and high mobility on the substrate surface. By varying cluster sizes and substrate temperatures, this study also reveals that smaller clusters and higher substrate temperatures contribute to faster structural ordering and smoother surface morphologies. Furthermore, the formed layers display a consistent SiGe composition, closely aligning with nominal values, and the cluster-assisted deposition method achieves the epitaxial bridging of heterostructures during cluster impingement, highlighting its additional distinctive characteristics. The implications of this work make it clear that the mechanism of fast alloyed epitaxial film growth by cluster-assisted mesoplasma CVD is critical for extending it as a versatile platform for synthesizing various epitaxial films.

Mesoporous silicas synthesized by the co-condensation of two and three different silica monomers were synthesized by varying the time intervals between the addition of individual monomers, while the total time interval was kept constant. This resulted in different structural properties of the final silicas, particularly in their porosity and local ordering. One of the obtained samples exhibited an unusual isotherm with two hysteresis loops and its total pore volume was as high as 2.2 cm3/g. In addition, to be thoroughly characterized by a wide range of instrumental techniques, the obtained materials were also employed as the adsorbents and release platforms of a diclofenac sodium (DICL; used here as a model drug). In the case of DICL adsorption and release, differences between the samples were also revealed, which confirms the fact that time control of a monomer addition can be successfully used to fine-tune the properties of organo-silica materials. [ABSTRACT FROM AUTHOR]

In this project, KIT-5 materials were effectively functionalized with sulfonic groups introduced by grafting or the co-condensation method and tested as heterogeneous solid acid catalyst. A co-condensation procedure leading to the stable, –SO3H functionalized KIT-5 materials was successfully established. Moreover, the influence of both synthesis methods on the structural and textural parameters, as well as surface chemistry, morphology, and catalytic activity of –SO3H/KIT-5 materials was thoroughly investigated. The syntheses with 3-mepkaptopropyltrimethoxysilane (MPTMS) acting as a modifying agent resulted in samples in which functional groups were introduced into the structure and/or onto the mesoporous silica surface. The oxidation stage of –SH to –SO3H groups was carried out under mild conditions, using a "green" oxidant (H2O2). The application of different functionalization techniques and the introduction of different amounts of modifying agent allowed for an evaluation of the influence of these parameters on the ordering of the mesoporous structure of KIT-5 materials. The applied methods of assessment of the physicochemical parameters (XRD, low-temperature N2 sorption, TEM) showed that, especially when the co-condensation method was applied, as the number of functional groups increased, the ordering of structure characteristic of KIT-5 decreased. On the other hand, the samples modified by grafting had a stable structure, regardless of the amount of introduced MPTMS. Test reactions carried out on the basis of Friedel–Crafts alkylation process showed that the synthesized materials can be considered promising acid catalysts in heterogeneous catalysis reactions. [ABSTRACT FROM AUTHOR]

Abstract The synthesis and characterization of amino‐functionalized mesoporous silica nanoparticles are presented following two different synthetic methods: co‐condensation and post‐synthesis grafting of 3‐aminopropyltriethoxysilane. The amino groups’ distribution on the mesoporous silica nanoparticles was evaluated considering the aggregation state of a grafted photosensitizer (Verteporfin) by using spectroscopic techniques. The homogeneous distribution of amino groups within the silica network is a key factor to avoid aggregation during further organic functionalization and to optimize the performance of functionalized silica nanoparticles in biomedical applications. In addition, the formation of a protein corona on the external surface of both bare and amino‐functionalized mesoporous silica was also investigated by adsorbing Bovine Serum Albumin (BSA) as a model protein. The adsorption of BSA was found to be favorable, reducing the aggregation phenomena for both bare and amino‐modified nanoparticles. Nevertheless, the dispersant effect of BSA was much more evident in the case of amino‐modified nanoparticles, which reached monodispersion after adsorption of the protein, thus suggesting that amino‐modified nanoparticles can benefit from protein corona formation for preventing severe aggregation in biological media.

Mesoporous silicas synthesized by the co-condensation of two and three different silica monomers were synthesized by varying the time intervals between the addition of individual monomers, while the total time interval was kept constant. This resulted in different structural properties of the final silicas, particularly in their porosity and local ordering. One of the obtained samples exhibited an unusual isotherm with two hysteresis loops and its total pore volume was as high as 2.2 cm3/g. In addition, to be thoroughly characterized by a wide range of instrumental techniques, the obtained materials were also employed as the adsorbents and release platforms of a diclofenac sodium (DICL; used here as a model drug). In the case of DICL adsorption and release, differences between the samples were also revealed, which confirms the fact that time control of a monomer addition can be successfully used to fine-tune the properties of organo-silica materials.

Biomolecular condensates provide distinct compartments that can localize and organize biochemistry inside cells. Recent evidence suggests that condensate formation is prevalent in the cell nucleus. To understand how different components of the nucleus interact during condensate formation is an important challenge. In particular, the physics of co-condensation of proteins together with nucleic acids remains elusive. Here we use optical tweezers to study how the prototypical prion-like protein Fused-in-Sarcoma (FUS) forms liquid-like assemblies in vitro, by co-condensing together with individual DNA molecules. Through progressive force- induced peeling of dsDNA, buffer exchange, and force measurements, we show that FUS adsorbing in a single layer on DNA effectively generates a sticky FUS–DNA polymer that can collapse to form a liquid-like FUS–DNA co-condensate. Condensation oc- curs at constant DNA tension for double-stranded DNA, which is a signature of phase separation. We suggest that co-condensation mediated by protein monolayer adsorption on nucleic acids is an important mechanism for intracellular compartmentalization. [ABSTRACT FROM AUTHOR]

Water vapor adsorption is a process of great importance for several industries. Because of that, new materials formed by mesoporous silica with metallic heteroatom functionalization have been studied for water adsorption. This functionalization process is still little studied in the literature, with many topics remaining to be evaluated. One of them is how each functionalization method (grafting and co-condensation) influences the generation of isomorphic substitution or extra-framework oxides. Another is which of these configurations is most interesting for water adsorption. This work aims to address both questions. For this, two groups of samples were synthesized using grafting and co-condensation for the insertion of Al, Ti, Zr and Li into mesoporous silica SBA-15. These samples were analyzed using nitrogen adsorption, high resolution scanning microscopy, energy dispersive X-ray spectroscopy, magic angle spinning nuclear magnetic resonance, Fourier transform infrared spectroscopy, pyridine adsorption and water adsorption. These techniques revealed that the co-condensation approach used in this work was most interesting for water adsorption at low partial pressures. This occurred because it generated a higher degree of isomorphic substitution, which was found to be the most active configuration of heteroatoms for this application. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of amino‐functionalized mesoporous silica nanoparticles are presented following two different synthetic methods: co‐condensation and post‐synthesis grafting of 3‐aminopropyltriethoxysilane. The amino groups' distribution on the mesoporous silica nanoparticles was evaluated considering the aggregation state of a grafted photosensitizer (Verteporfin) by using spectroscopic techniques. The homogeneous distribution of amino groups within the silica network is a key factor to avoid aggregation during further organic functionalization and to optimize the performance of functionalized silica nanoparticles in biomedical applications. In addition, the formation of a protein corona on the external surface of both bare and amino‐functionalized mesoporous silica was also investigated by adsorbing Bovine Serum Albumin (BSA) as a model protein. The adsorption of BSA was found to be favorable, reducing the aggregation phenomena for both bare and amino‐modified nanoparticles. Nevertheless, the dispersant effect of BSA was much more evident in the case of amino‐modified nanoparticles, which reached monodispersion after adsorption of the protein, thus suggesting that amino‐modified nanoparticles can benefit from protein corona formation for preventing severe aggregation in biological media. [ABSTRACT FROM AUTHOR]

Mesoporous silicas are known to be high-performing water adsorbents in high humidity levels due to their large pore volumes. However, for low humidity conditions, these materials typically present a less expressive performance, which is a drawback for many applications. In the present report, mesoporous silica SBA-15 was functionalized with Al, Ti, Zr and Li in order to improve their performance in this condition. The influence of functionalization in porosity, morphology and acidic sites was investigated. Samples with an increased number of acidic sites and with higher microporosity when compared to pure silica were produced. This was responsible for their enhanced performance for water adsorption in low moisture conditions. Sample functionalized with zirconium in SBA-15 synthesis improved the water adsorption capacity of pure silica by three times, reaching up to 127 g kg−1 at a relative pressure of 0.2 and 570 g kg−1 close to saturation pressure. This sample was found to be a promising material to be applied in processes which require high adsorption capacities in both low and high water partial pressure ranges. Moreover, the understanding of the mechanisms behind the heteroatom functionalization can be applied to any silica material in order to enhance its attractiveness towards any polar molecule. [ABSTRACT FROM AUTHOR]

The process of organoyttriumoxanealumoxanes co-condensation with chromium acetylacetonate has been studied, as a result chromium-containing organoyttriumoxanealumoxanes were obtained, which are ceramic-forming oligomers and may have fiber-forming properties. Their physicochemical characteristics have been determined by NMR, IR spectroscopy, SEM, TGA, XRD and elemental analysis. It has been found that when the molar ratio of chromium-containing organoyttriumoxanealumoxanes is Al/Y ≈ 2 and Al/Cr ≈ 180 they have fiber-forming properties. Polymer fibers were produced from chromium-containing organoyttriumoxanealumoxanes by melt spinning. The process of thermochemical transformation of synthesized chromium-containing organoyttriumoxanealumoxanes into the ceramic phase has been studied. It is found out that the pyrolysis of chromium-containing organoyttriumoxanealumoxanes leads to the formation of Y3(CrxAl1−x)5O12, YAlyCr1-yO3 and α-(Al2−xCrxO3). That is, these oligomers can be used to create a new generation of heatresistant, optically-transparent, corrosion—and radiation-resistant multicomponent ceramics based on aluminum, yttrium and chromium oxides. [ABSTRACT FROM AUTHOR]

Since stationary phase is the key to chromatographic separations, it is worth pursuing simpler and more efficient methods for preparing chromatographic stationary phases. In this work, co-condensation and pseudomorphic transformation were combined to prepare a functionalized shell on the surface of the silica core in one step, and different kinds of silylation reagents were used to investigate the self-assembly mechanism. 3-Mercaptopropyltriethoxysilane facilitated the formation of the shell during pseudomorphic transformation, and sulfhydryl groups were distributed in the shell uniformly. These core-shell particle were applied in hydrophilic chromatography and ion-exchange chromatography successfully after the oxidation of the sulfhydryl groups to sulfonic acid groups. Pseudomorphic transformation with silylated reagents has the advantage of rapid preparation of chromatographic stationary phases with good reproducibility. [Display omitted] • Co-condensation and pseudomorphic transformation methods were combined to prepare the core-shell particles. • Functionalized mesopores were formed on the surface of solid silica cores in one step. • Self-assembly mechanism was explored to explain the different impacts of silylation reagents. • Core-shell particles can be served as stationary phases for chromatography. [ABSTRACT FROM AUTHOR]

An efficient solventless one-pot procedure for the synthesis of imidazolium-based ionic liquid under microwave irradiation is described in which 1-methylimidazole was modified by organosilane (3-chloropropyl triethoxysilane). This ionic liquid 1-methyl-3-[(triethoxysilyl)propyl]imidazolium chloride (TMICl) is immobilized on Mechanically activated Fly Ash (MFA) by co-condensation method to develop an active organocatalyst (TMICl/MFA). The mechanical activation has generated significant number of silanol groups suitable for immobilizing ionic liquids. For characterization of various materials, different techniques viz, XRD, FTIR, SEM-EDX, TGA, BET surface area, H1NMR are used. The prepared TMICl/MFA exhibited high catalytic activity for a series of microwave assisted esterification of aliphatic alcohols and salicylic acid for four successive reaction cycles under optimized conditions.

A simple one-pot synthesis process for functionalized mesostructured silica nanoparticles (MSNP) is reported. The novel process demonstrated the possibility to achieve MSNP with a surface area up to 501 m2.g−1 using a phosphonate based nonsilane precursor such as N, N´-bis[4,6-bis(diethylphosphono)-1,3,5-triazin-yl]-1,2-diaminoethane (ED). MSNP obtained by using 20 mol% of ED achieved a surface area of 80 m2.g−1 and increasing the ED content to 30 mol% resulted in a surface area of 501 m2.g−1. Zeta potential of novel MSNPs (−65.5 and 70.0 mV) were much higher than the nanoparticle (NP) prepared from only TEOS (−49 mV), indicating the presence of a large number of –SiOH and phosphonic acid surface functional groups, as confirmed by Fourier-transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance (NMR) analysis. The functionalized MSNPs were used as an adsorbent for the removal of cationic pollutants like methylene blue (MB). The MSNP with the highest porosity displayed favorable MB adsorption behavior with ~380 mg.g−1 of MB adsorption capacity. Facile regeneration in an acidic medium (~pH 4.5) with easy recyclability (10 cycles) confirmed the practical applicability of this novel functionalized MSNPs.

Vinyl, chloropropyl, and mercaptopropyl functionalized particles were prepared by a two‐step acidic/alkaline catalyzed co‐hydrolysis/condensation of methyltrimethoxysilane with a different silane precursor that carries chemically reactive functional group including vinyl, chloropropyl, and mercaptopropyl, respectively. The morphology, pore structure, and functional groups of the synthesized packings were studied by SEM, nitrogen adsorption‐desorption measurements, and solid‐state 13C 29Si NMR spectroscopy, respectively. The particles show ordered sphere, narrow particle size distribution, and mesoporous structure. The carbon contents of the microspheres are in the range of 17–19%, comparable to those of octadecyl‐bonded silica packings. The three‐kind of microspheres were directly used as packing materials for high‐performance liquid chromatography without size classification. The chromatographic performance of the columns was evaluated and compared with a commercially available C18 phase. The results revealed that these columns possess typical reversed‐phase chromatographic properties with increased hydrophobicity than polymethylsilsesquioxane and symmetric peaks for basic compounds. They were applied to the simultaneous separation of combination bendazol hydrochlorothiazide capsules containing polar and basic drugs with peaks identified by tandem with mass spectrometry. In general, a novel method is provided for the synthesis of different methyltrimethoxysilane‐derived microspheres for high‐performance liquid chromatography, which are advantageous for separating basic compounds. [ABSTRACT FROM AUTHOR]

Phase separation is one key mechanism to organize chromatin into compartments and to regulate the activity of the genome. The formation of liquid-like droplets within the nucleus is driven by protein association to the DNA via multivalent binding and the recruitment of other proteins building a concentrated reaction environment. Common methods to study phase separation and its liquid-like nature are based on microscopy of the formed droplets but lack the resolution to obtain information on the molecular level. Here, we describe the application of the DNA curtain technique for studying protein-mediated phase separation on DNA. For this, multiple lipid-anchored DNA strands are flow-stretched across a nanobarrier to allow single-molecule studies of protein-DNA interactions in a high-throughput approach. Our protocol describes how protein-induced DNA compaction can be observed in real-time and which wash protocols are suitable to characterize the interactions that promote condensate formation. Furthermore, we demonstrate how fluorescently labeled tracer proteins can serve as orientation points to examine the DNA compaction mechanism in detail., (Copyright © 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.)

An approach to p-tert-butylthiacalix[4]arene derivatives functionalized with lactic acid fragments in three conformations (cone, partial cone, 1,3-alternate) was developed. The use of tetraglyme as a solvent and magnesium sulfate with p-toluenesulfonic acid as co-condensation catalysts made it possible to obtain the desired products without admixtures of oligolactic acid. The structure of the synthesized macrocycles was characterized by a complex of physico-chemical methods. The thermal properties of the synthesized lactic acid copolyesters were studied by simultaneous thermogravimetry and differential scanning calorimetry analysis. Significant effect of the p-tert-butylthiacalix[4]arene platform on the thermal stability of the obtained products was demonstrated. Nanoscale particles of the synthesized macrocycles with a low polydispersity index were obtained using nanoprecipitation from methanol or acetone into a buffer solution. [ABSTRACT FROM AUTHOR]

• This review covers the recent progress in the design and engineering of multifunctional silica-supported cooperative catalysts. • The concept of cooperative catalysis is briefly presented. • The different synthetic methods for the preparation of multifunctional silica-supported cooperative catalysts are described. • Critical factors such as the ratio, the proximity and the distribution of surface catalytic groups are discussed. The immobilization of multiple functional groups on mesoporous silica has provided opportunities to emulate the unique design principles and performances of enzymes. In this direction, it is essential to master the cooperative behavior of active surface-bound molecules to arrive at heterogeneous, recyclable catalysts with enhanced or novel properties compared to the parent system in solution. With the advances in sol-gel and surface chemistry, it is now possible to prepare silica-supported multifunctional catalysts that can combine most of the activation modes of organic chemistry. Further tailoring the surface ratio and proximity of the confined activating functional groups affords ways to refine the probability of synergistic interactions within the active site. Yet, the systematic evaluation and engineering of the spatial distribution of surface functional groups, which are more often randomly arranged within the pore channels, rises the next key challenge towards a more rational design of bioinspired supported catalysts. [ABSTRACT FROM AUTHOR]

Abstract Amino-functionalized mesoporous MCM-41 materials were synthesised by co-condensation of amino-organosiloxane precursors, namely 3-aminopropyltrimethoxysiloxane (APS), 3-(methylamino)propyltrimethoxysiloxane (MAPS) and 3-(phenylamino)propyltrimethoxysiloxane (PAPS) with tetraethyl orthosilicate (TEOS) in water solution containing ammonia and in the presence of surfactant as templating agent. The ratio of amino-organosiloxanes to TEOS in the synthesis mixture was 3, 5, 10, 20 and 30 wt%. The prepared samples were characterized by Small Angle X-ray Scattering (SAXS), High-Resolution Transmission Electron Microscopy (HRTEM), Thermogravimetric Analysis (TGA) and N 2 adsorption/desorption. It followed from the measurements that the ordered porous materials of hexagonal symmetry were obtained at small ratios of APS and MAPS to TEOS (3, 5, 10 wt%). At larger ratios (20 and 30 wt%), disordered or non-porous amorphous amino-functionalized silica particles were obtained. For the PAPS precursor, hexagonally-packed structures were observed up to a PAPS to TEOS ratio of 30 wt%, when a transition to a lamellar phase occurs. The reasons of the structural changes are discussed in terms of modifications in the effective shapes of the cylindrical micelle aggregates, caused by different hydrophilicity/hydrophobicity of the used amine precursors and their interactions with surfactant micelles. To better understand the origin of this behavior, lattice Monte Carlo simulations of simple coarse-grained surfactant solutions were performed. All prepared samples were used to study CO 2 adsorption. It was found that CO 2 adsorption capacity in the samples increased with the increasing concentration of amino-organosiloxane precursor, independently of the surface area. These results imply that CO 2 adsorption primarily takes place on amine active centers and physical adsorption, which is dependent on the high surface area, plays a less important role in CO 2 adsorption on these materials. Graphical abstract Unlabelled Image Highlights • Experimental and molecular modelling study showed on phase change in silica. • Mesophase control by tuning of the hydrophobicity of the functional amine group • Different hydrophobicity of amine precursors caused modifications in micelle aggregates. • Disordered or lamellar structures were observed at higher ratios of amines to TEOS. • CO 2 adsorption capacity increased with increasing concentration of amine precursors. [ABSTRACT FROM AUTHOR]

Mesoporous silica particles have been prepared with functionalized precursors, used either in situ co-condensation process or as post-synthesis grafting agents, in order to deliver surface functionalisation. Aminopropyl, mercaptopropyl, vinyl and hexyl organosilanes were used as funtionalized precursors, tetraethyl orthosilicate as the base silica precursor material, hexadecyl-trimethylammonium bromide (CTAB) as directing agent and water-ethanol mixture as solvent, with ammonia catalyst. The aim was to explore the effect of various recipes on the structural properties of the composite materials. The samples' microstructures have been evaluated using nitrogen sorption and small angle neutron scattering. Ordered mesoporous structures were obtained, for almost all synthesis conditions, after the solvent-extraction of the template agent. Only in one case, for the materials functionalized by mercaptopropyl groups in co-condensation route, disordered amorphous structure was obtained. All samples functionalized by post-grafting presented well-ordered mesoporous structures. The results have potential use for easy design of sorbent materials for drug loading or pollutant adsorption applications. [ABSTRACT FROM AUTHOR]

Abstract RAFT mesoporous silica nanoparticles (MSNs) have been synthesized for the first time via co-condensation of an organoalkoxysilane RAFT agent, 1-phenylethyl(3-(triethoxysilyl)propyl)carbonotrithioate, with tetraethoxysilane (TEOS) in aqueous basic cetyltrimethylammonium bromide. The stability of the organoalkoxysilane RAFT agent during the synthesis of MSNs was established using solution NMR and UV–visible spectroscopies. The RAFT-MSNs were then used for elaboration with N -isopropylacrylamide (NIPAM) via controlled surface-initiated RAFT polymerization. The success of the incorporation of the organoalkoxysilane RAFT agent into the silica network, and polymerization of PNIPAM was confirmed with TGA, FT-IR, UV–visible spectroscopy, 13C and 29Si solid state NMR spectroscopy. The effect of the organoalkoxysilane based RAFT agent and PNIPAM grafting on the morphology, size and surface area of the resulting MSNs was investigated using SEM, TEM, XRD, DLS and BET analysis. The appearance of carbon signals in 13C solid state NMR, T signals in 29Si solid state NMR and C H stretching signals in FT-IR establishes that we have successfully obtained organic-inorganic hybrid materials. The pore area calculated using Barrett-Joyner-Halenda (BJH) analysis was 87.8 m2 g−1 for control-MSNs, 91.1 m2 g−1 for RAFT-MSNs and 132.9 m2 g−1 for PNIPAM-MSNs. The thermoresponsive behaviour of PNIPAM grafted inside the pores of MSNs was studied by dye as well as drug loading experiments at variable temperatures, followed by characterization using confocal laser scanning microscopy. The green and red fluorescence corresponding to fluorescein and doxorubicin respectively was strongly retained in the PNIPAM-MSNs after 24 h of incubation at 25 °C while lack of fluorescence after 24 h incubation at 35 °C, demonstrates the thermoresponsive behaviour of the polymer being grafted inside the pores of mesoporous silica nanoparticles. Graphical abstract Image 1 Highlights • RAFT mesoporous silica nanoparticles have been synthesized via co-condensation of an organoalkoxysilane RAFT agent and tetraethoxysilane. • The success of incorporation of RAFT agent and polymerization of PNIPAM was confirmed using FT-IR, UV-visible, and solid state NMR spectroscopy. • The effect of RAFT agent and PNIPAM grafting on the morphology, size and surface area was investigated using SEM, TEM, XRD, DLS and BET analysis. • The thermoresponsive behaviour of PNIPAM grafted MSNs was studied by dye as well as drug loading experiments and characterization using CLSM. [ABSTRACT FROM AUTHOR]

Classical halides of the heavier Group 14 homologues germanium, tin, and lead are common precursors for the synthesis of exciting compounds, such as polyhedral clusters. To get access to larger metalloid cluster compounds of Group 14, the disproportionation reaction of metastable monohalide solutions, accessible through a preparative co‐condensation reaction, proved to be quite successful. As the identity of the subvalent halides within the metastable solutions were yet unknown the reaction course from a monohalide precursor to a metalloid cluster was mostly unidentified. This might change now, as a first subhalide cluster [Ge14Br8(Et3P)4] could be characterized, being the first trapped intermediate of the disproportionation reaction of Group 14 subhalides. All these aspects are included within this Minireview, together with a short historical overview, dealing with the development of the preparative co‐condensation technique out of the matrix isolation technique, being the essential first step of the synthesis of metastable monohalide solutions of the heavier Group 14 elements Ge and Sn. Metastable solutions of monohalides of germanium and tin open the door for the synthesis of element‐rich metalloid clusters by means of a disproportionation reaction. In this Minireview recent developments are discussed, highlighting the first structurally characterized metalloid subhalide cluster of Group 14—[Ge14Br8(Et3P)4]—giving first insight into the complex reaction mechanism of the disproportionation reaction. [ABSTRACT FROM AUTHOR]

Abstract Aminopropyl modified mesoporous SiO 2 nanoparticles, MCM-41 type, have been synthesized by the co-condensation method from tetraethylorthosilicate (TEOS) and aminopropyltriethoxysilane (APTES). By means of modifying TEOS/APTES ratio we have carried out an in-depth characterization of the nanoparticles as a function of APTES content. Surface charge and nanoparticles morphology were strongly influenced by the amount of APTES and particles changed from hexagonal to bean-like morphology insofar APTES increased. Besides, the porous structure was also affected, showing a contraction of the lattice parameter and pore size, while increasing the wall thickness. These results bring about new insights about the nanoparticles formation during the co-condensation process. The model proposed herein considers that different interactions stablished between TEOS and APTES with the structure directing agent have consequences on pore size, wall thickness and particle morphology. Finally, APTES is an excellent linker to covalently attach active targeting agents such as folate groups. We have hypothesized that APTES could also play a role in the biological behavior of the nanoparticles. So, the internalization efficiency of the nanoparticles has been tested with cancerous LNCaP and non-cancerous preosteoblast-like MC3T3-E1 cells. The results indicate a cooperative effect between aminopropylsilane presence and folic acid, only for the cancerous LNCaP cell line. Highlights • Silica mesoporous nanoparticles have been selectively functionalized with amine and folate groups. • The particles morphology and surface charge are strongly dependent on the organosilane content. • A model explaining the influence of aminopropyl groups on the mesoporous structure is proposed. • A cooperative effect between folate and amine groups occurs only in tumoral cells overexpressing folate binding proteins. [ABSTRACT FROM AUTHOR]

The adsorptive potential has been evaluated for the aminopropyl functionalized mesoporous silica materials obtained by co-condensation and post grafting methods. Nitrogen sorption, small angle neutron and X-ray scattering (SANS and SAXS) demonstrated high surface area and well-ordered hexagonal pore structure suitable for applications as adsorbents of metals from waste waters. A comparison of Cr(VI) adsorption properties of the materials prepared by different functionalization methods has been performed. The obtained results demonstrated the adsorption capacity due to the affinity of the chromium ions to the amino groups, and showed that co-condensation of tetraethoxysilane (TEOS) and 3-aminopropyl triethoxysilane (APTES) resulted in higher metal sorption capacity of the materials compared to post-synthesis grafting of aminopropyl groups onto the mesoporous silica particles.

• A VLE study on C 6 /H 2 O at T = 183.7–214.7 °C and at P = 2.5 MPa is reported. • VLE results are presented in a T-xy diagram. • Azeotropic co-condensation at 183.7 °C and x C 6 =0.6029 was observed. • VLE data were modeled by CPA EoS and NRTL model. • Activity coefficient and infinite dilution activity coefficient are estimated. We report the vapor-liquid equilibria (VLE) of the binary mixture of the n-C 6 /H 2 O system at P =2.5 MPa and T =(456.85 – 487.85 K). The result showed an azeotropic behavior with a co-condensation temperature of ∼456.85 K at an n-C 6 mole fraction of ∼0.6029. The measured experimental data are modeled with the Cubic Plus Association Equation of State (CPA-EoS) and activity coefficient-based Non-Random Two Liquid (NRTL) model. The infinite dilution activity coefficient of n-C 6 and H 2 O are also estimated over the temperature range of interest. The overall root mean square deviation (RMSD) of the n-C 6 mole-fraction in vapor and liquid phases for the CPA EoS and NRTL models are 0.0370 and 0.0765, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanotechnology has a prominent potential in biomedical and biomedicine applications. Especially, owing to their exclusive characteristics, hybrid nanocompounds have been recently considered as promising systems for imaging and therapeutic usages. Study on silica-based mesoporous silica materials as drug delivery systems has been considerably developed over the recent few years due to the excellent versatility and stability of these mesoporous materials. In this review, the advanced developments in synthesis, functionalization and application of mesoporous silica in drug delivery are introduced. The first section consists of three main methods, grafting, co-condensation, and periodic mesoporous organosilicates. In the next part, new approaches for functionalization of mesoporous silica in order to control drug delivery are explained. The superiority of mesoporous nannoparticles for numerous drug delivery applications are also summarized. Different mesoporous silica structures can be designed by various chemical methods to meet the drug delivery requirements. The accessible channels in mesoporous which may act as reservoirs for storing drugs can be opened and closed by different systems and create stimuli-responsive release carriers. This review focuses on intelligent nanomaterials based on mesoporous silica which can be stimulated by chemical or biological signals, such as pH, temperature, light, magnetic field and enzymes.

For the very first time, ordered mesoporous hydrotalcite like compound containing Mg, Al and Co was prepared through co-condensation and co-condensation-evaporation methods using CTAB as a structure directing agent. The co-condensation and co-condensation-evaporation methods were established at 80 °C for 48 h under alkaline media followed by drying and calcination at 400 °C for 3 h for removing the directing agent from the porous system. Controlling pore width of the material was also studied by applying two method: hydrothelmal treatment and using another template. The results confirmed that the co-condensation-evaporation method was better than the co-condensation one because it could produce high ordered mesoporous channels. The controlling also pointed out that bothe methods could be used for narrowing and reducing the pore width of the material. Structural charactizations of these two materials were analyzed by many techniques including Small Angle X-Ray Diffraction (SAXRD), Wide Angle X-Ray Diffraction (WAXRD), Transmission Electron Microscopy (TEM) and Brunauer, Emmett and Teller Theory (BET). [ABSTRACT FROM AUTHOR]

Organic functionalization of periodic mesoporous silicas (PMSs) is an imperative and effective measure to advance their preeminent properties and widespread application due to their structural superiority. In this study, we reported a novel synthesis of organic functionalized PMSs by co-condensing (R’O) 3 Si-H and (R’O) 3 Si-R type terminal trialkoxyorganosilanes based on periodic mesoporous hydridosilica, which is stable but pore walls are comprised of a three-connected three-dimensional network. The synthesis extended the “co-condensation” strategy and broke the incorporation limitation of organic groups by HSiO 3 units in the framework to form hydrogen bonds, which provided a more effective way to obtain PMSs with high degree of organic functionalization. [ABSTRACT FROM AUTHOR]

Ferrocenylazobenzene-functionalized mesoporous MCM-41 material (Fc-Az-M14), was synthesized directly through co-condensation of 4-triethoxysilyl-3′-ferrocenylazobenzene (TEFA) and tetraethyl orthosilicate (TEOS), under basic conditions, using cetyltrimethylammmonium bromide (CTAB) as structure-directing agent. The template was removed through solvent extraction, to yield the ferrocenylazobenzene-containing ordered mesoporous organosilicas Fc-Az-M41. The prepared material was characterized by nitrogen adsorption, X-ray diffraction (XRD), solid state 29 Si MAS NMR and 13 C CP-MAS NMR, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Thermogravimetric analysis (TGA) and diffuse reflectance UV-Vis spectroscopy (DR UV). The results showed that Fc-Az-M41 had an ordered two-dimensional hexagonal mesostructure, high BET surface area and pore volume. The pore diameter, BET surface area, and pore volume of the extracted material were 3.8 nm, 1070 m 2 /g and 0.80 cm 3 /g, respectively. The mean pore diameters of MCM-41 clearly decreased by ca. 0.65 nm upon incorporation of Fc-Az groups. UV-Vis spectrum of Fc-Az-M41 was determined by a diffuse reflectance method after UV irradiation. The presence of the azobenzene chromophores in this material can be clearly observed in the DR UV-Vis spectra of surfactant-free Fc-Az-M41. This spectra shows that the framework of this material is formed predominantly by trans isomer, and the π - π * and the n - π * absorption bands were affected by metal-to-ligand charge transfer (MLCT). [ABSTRACT FROM AUTHOR]

A novel amino-functionalized multiwalled carbon nanotube (MWCNTs @SiO 2 -NH 2 ) was prepared via co-condensation using etraethyl orthosilicate and 3-aminopropyl trimethoxysilane for effective removal of Pb(II) from water. The Pb (II) adsorption efficiencies of MWCNTs and MWCNTs@SiO 2 -NH 2 were compared and the change of morphology features was assessed in batch adsorption experiments. The characterization analysis like XRD, FITR and XPS revealed that amino groups were successfully grafted on the MWCNTs. Adsorption results demonstrated that the best TEOS/APTMS loading ratio was about 10:3 based on their solution volume ratio. Compared to the poor Pb(II) adsorption capacity of pristine MWCNTs, the maximum adsorption capacity of MWCNTs@SiO 2 -NH 2 was greatly improved to 147 mg/g after amination treatment. Pb(II) adsorption onto MWCNTs@SiO 2 -NH 2 was strongly pH-dependent and the optimal aqueous pH was about 5. Moreover, the pseudo-second-order kinetics model and Langmuir isotherm model could well describe the Pb(II) adsorption process by MWCNTs@SiO 2 -NH 2 . Thermodynamics analysis illustrated that the Pb(II) adsorption was spontaneous and endothermic. FTIR and XPS analysis of MWCNTs@SiO 2 -NH 2 after adsorption demonstrated the complexation between amino groups and Pb(II) played a vital role in the adsorption mechanism. Findings from the present study suggested that successful Pb(II) removal could be achieved using such novel adsorbent composite with optimized process. [ABSTRACT FROM AUTHOR]

Well-defined spherical particles of silica, containing phenyl group, with the diameter of ca. 2 microns were prepared by the co-condensation of tetraethoxysilane with phenyltriethoxysilane in basic aqueous methanol solutions of hexadecyltrimethylammonium chloride. The products were hydrophobic. The content of phenyl group was controlled by the ratio of tetraethoxysilane and phenyltriethoxysilane in the starting solution. Hexadecyltrimethylammonium was extracted with methanolic HCl to obtain nanoporous silica spherical particle containing phenyl group. The spherical particle possessed pore size of 1.8 nm and the BET surface area of 750 m2 g−1. [ABSTRACT FROM AUTHOR]

Abstract: Novel and advanced catalysts based on Ni‐Ga alloy were prepared through co‐condensation method with and without evaporation of water solvent for converting CO2 to methanol. The co‐condensations used Ni(NO3)2 and Ga metal as beginning precursors under alkaline media. Various Ni/Ga molar ratios and temperature of the co‐condensation‐evaporation method were investigated in order to obtain Ni5Ga3 alloy composition as active phase for the catalysts. The results confirmed that the stoichiometry of 5/3 could be reached at the same molar ratio of the beginning precursors, and the suitable temperature of the method was 80 °C for a certain time of 24 h. The Ni‐Ga based catalyst activity and selectivity were also tested in the conversion of CO2 to methanol at atmospheric pressure and 220 °C for different periods of time. The results showed that the catalyst was an excellent candidate for this process compared to other catalysts when exposing good selectivity over 90 % during long periods of time. Many techniques were used including X‐Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), X‐Ray Photoelectron Spectroscopy (XPS), Nitrogen Adsorption–Desorption Analysis (BET), and Gas Chromatography (GC) to characterize the catalyst structure and the reaction performance, respectively. [ABSTRACT FROM AUTHOR]

Furfural, as an organic compound derived from biomass materials, was used to partially substitute for formaldehyde in the synthesis of UF resin. Urea-formaldehyde-furfural co-condensed (UFFR) resins with different substitute ratios of furfural to formaldehyde (FR/F) were prepared. The effects of the FR/F substitute ratio on the performances of UFFR resins were investigated. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) and Fourier transform infrared spectroscopy (FT-IR) were applied to characterize the chemical structures of UFFR resins. Plywood bonded by these resins was manufactured, and its bond strength and formaldehyde emission were measured. The results showed that the substitution of furfural in place of formaldehyde could reduce the free formaldehyde content effectively at the expense of prolongation of the curing time. The spectra of MALDI-TOF and FTIR confirmed the co-condensation of urea-formaldehyde-furfural both in uncured and cured resins. Plywood prepared under optimized parameters could yield high bond strength and low formaldehyde emission, which were 0.84 MPa and 0.23 ppm, respectively. The optimized parameters were as follows: a FR/F substitute ratio of 1/3; 1% (NH4)2S2O8 as the curing agent; and a hot pressing temperature of 130 °C. Hence, it is feasible to substitute partially formaldehyde by furfural to prepare UFFR resins as wood adhesives for plywood.

We report on the facile synthesis of g-CN based polymers by co-condensing urea with glycine for photocatalytic hydrogen evolution. The as-prepared photocatalysts were then characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, UV-Vis diffuse reflectance spectroscopy, photoluminescence emission spectrometry, electron paramagnetic resonance spectrometry and transmission electron microscopy. Compared with pristine g-CN, obtained from direct pyrolysis of urea, the CNU-G photocatalyst showed largely enhanced photocatalytic H activities about 75 μmol h, which is 5 times higher than of the pristine CNU. The enhanced activities are ascribed to the larger specific area surface, strengthened optical absorption and improved electron transport ability. Our work opens up a new pathway for the synthesis graphitic carbon nitride photocatalysts with glycine modification to enhance photocatalytic activities. [ABSTRACT FROM AUTHOR]

Antioxidant in form of hindered phenol structure is commonly used to prolong the service life of polymer, while the low molecule antioxidant has defect for its low thermal stability and physical loss. Herein, the feasibility of using co-condensed silica immobilized antioxidant (denoted as SN-NH 2 -AO) to improve the thermal-oxidative stability of polypropylene (PP) was evaluated. Firstly, SN-NH 2 -AO was prepared by immobilization of 3,5-di- tert -butyl-4-hydroxyphenylpropionic acid (AO) on the surface of co-condensed silica (SN-NH 2 ) which was synthesized by co-hydrolysis and condensation of tetraethoxysilane and aminopropyltriethoxysilane. Compared with AO, SN-NH 2 -AO exhibited higher thermal stability. Further, SN-NH 2 -AO was incorporated into PP by melt blending. The incorporation of SN-NH 2 -AO could not only disperse well in PP matrix but also improve the thermal-oxidative stability of PP distinctly. It was found that although the anti-oxidative efficiency of SN-NH 2 -AO was slightly inferior to AO, SN-NH 2 -AO exhibited superiority on anti-extraction property. [ABSTRACT FROM AUTHOR]

1,3-dimethylurea (DMU) was used tomimic urea and tomodelmelamine-urea-formaldehyde (MUF) co-condensation reactions. The products of 1,3-dimethylurea-formaldehyde (DMUF), melamine-formaldehyde (MF), and melamine-1,3-dimethylurea-formaldehyde (MDMUF) reactions under alkaline and weak acidic conditions were compared by performing quantitative carbon-13 nuclear magnetic resonance (13C-NMR) analysis. The effect of pH on the co-condensation reactions was clarified. With the presence of the methyl groups in DMU, the appearance or absence of the featured signal at 54-55 ppm can be used to identify the co-condensed methylene linkage -N(-CH3) -CH2-NH-. Under alkaline condition, MDMUF reactions produced primarily MF polymers and the featured signal at 54-55 ppm was absent. Even though the co-condensations concurrently occurred, undistinguishable and very minor condensed structures with ether linkage were formed. Differently, under weak acidic condition, the relative content of co-condensed methylene carbons accounts for over 40%, indicating the MDMUF co-condensation reactions were much more competitive than the self-condensations. The formation of reactive carbocation intermediate was proposed to rationalize the results. [ABSTRACT FROM AUTHOR]

Novel stable carboxylic acid derivatized alkoxy silanes are co-condensed with tetraethyl orthosilicate in the presence of a structure-directing agent in a direct 'one-pot' synthesis to porous carboxy-modified silica particles. Special emphasis is given to the influence of an increasing amount of 5-(triethoxysilyl)pentanoic acid and sodium hydroxide on the morphology and porous structure of the co-condensation products. The simultaneous conversion of both silanes resulted in the formation of mesoporous, monodisperse spherical particles with diameters between 100 and 140 nm and specific surface areas up to 900 m g. Additionally, adsorption equilibrium studies were performed, in which the particles modified with carboxylic acid groups showed an increased adsorption rate toward methylene blue compared to pure silica materials. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Acetate-functionalized silica membranes were prepared via co-condensation. The molar ratio of functional groups in the silica matrix was varied in the range of 0–0.6, denoted by x. The presence of functional groups bonded to the silica network was revealed by FTIR and 29 Si and 13 C solid-state NMR analysis. The stability of the groups was studied by TG analysis. The membranes were evaluated for CO 2 /N 2 mixture separation in a temperature range of 253–373 K using a feed pressure of 9 bar and a sweep gas kept at atmospheric pressure on the permeate side. The membranes were found to be CO 2 -selective at all the conditions studied. The highest observed selectivity was 16 for x=0.4, with a CO 2 permeance of 5.12×10 −7 mol s −1 m −2 Pa −1 . For x=0.2, a permeance of as high as 20.74×10 −7 mol s −1 m −2 Pa −1 with a CO 2 /N 2 selectivity of 7.5 was obtained. This permeance is the highest reported for CO 2 /N 2 separation using functionalized silica membranes. It is proposed that the separation mechanism between CO 2 and N 2 was the preferential adsorption of CO 2 , which inhibited adsorption and permeation of N 2 through the silica pore network. Permporometry results revealed that as the loading of functional groups increased, the He permeance decreased. It was also indicated that the quantity of micropores in the functionalized membrane was higher than that in the parent silica membrane. [ABSTRACT FROM AUTHOR]

A Mobil Composition of Matter (MCM)-41 type mesoporous silica material containing N-propylacridone groups has been successfully prepared by co-condensation of an appropriate organic precursor with tetraethyl orthosilicate (TEOS) under alkaline sol–gel conditions. The resulting material was fully characterized by means of X-ray diffraction (XRD), N2-adsorption–desorption, transmission electron microscopy (TEM), IR and UV–vis spectroscopy, as well as 29Si and 13C CP-MAS NMR techniques. The material features a high inner surface area and a highly ordered two-dimensional hexagonal pore structure. The fluorescence properties of the organic chromophore can be tuned via complexation of its carbonyl group with scandium triflate, which makes the material a good candidate for solid state sensors and optics. The successful synthesis of highly ordered MCM materials through co-condensation was found to be dependent on the chemical interaction of the different precursors.

The most fruitful synthetic route to metalloid tin clusters applies the disproportionation reaction of metastable Sn(I) halide solutions, whereby Si(SiMe3)3 is mostly used as the stabilizing substituent. Here, we describe the synthesis and application of the slightly modified substituent Ge(SiMe3)3, which can be used for the synthesis of metalloid tin clusters to give the neutral cluster Sn10[Ge(SiMe3)3]6 as well as the charged clusters {Sn10[Ge(SiMe3)3]5}− and {Sn10[Ge(SiMe3)3]4}2−. The obtained metalloid clusters are structurally similar to their Si(SiMe3)3 derivatives. However, differences with respect to the stability in solution are observed. Additionally, a different electronic situation for the tin atoms is realized as shown by 119mSn Mössbauer spectroscopy, giving further insight into the different kinds of tin atoms within the metalloid cluster {Sn10[Ge(SiMe3)3]4}2−. The synthesis of diverse derivatives gives the opportunity to check the influence of the substituent for further investigations of metalloid tin cluster compounds.

The synthesis by co-condensation of mesostructured cellular foam (MCF) functionalized with propyl-polyethylenimine (pPEI) was performed and the capability of this material to extract cadmium cations from aqueous solutions was investigated. Experiments revealed that under specific conditions of pH (pH = 5) and temperature (T = 295 K), the removal efficiency of Cd 2+ at concentrations ranging from 25 to 400 ppm, exceeded 90%. Adsorption isotherm fitted perfectly Langmuir and Freundlich models. Thermodynamic studies indicated that the adsorption process was spontaneous, endothermic and accompanied with structural modification of the adsorbent, the formation of metal complexes. The regeneration of the adsorbent was achieved by an acid-base treatment. The material was found to be stable after 3 cycles of adsorption–desorption as the uptake capacity remained unchanged. [ABSTRACT FROM AUTHOR]

New hybrid organic-inorganic mesoporous silicas were prepared by employing three different synthesis routes and mercury adsorption studies were done in aqueous media using the batch technique. The organic ligands employed for the functionalization were derivatives of 2-mercaptopyrimidine or 2-mercaptothiazoline, and the synthesis pathways used were post-synthesis, post-synthesis with surface ion-imprinting and co-condensation with ion-imprinting. The incorporation of functional groups and the presence of ordered mesopores in the organosilicas was confirmed by XRD, TEM and SEM, nitrogen adsorption-desorption isotherms, 13 C MAS-NMR, 29 Si MAS-NMR, elemental and thermogravimetric analysis. The highest adsorption capacity and selectivity observed was for the material functionalized with 2-mercaptothiazoline ligand by means the co-condensation with ion-imprinting route (1.03 mmol g −1 at pH 6). The prepared material could be potential sorbent for the extraction of this heavy metal from environmental and drinking waters. [ABSTRACT FROM AUTHOR]