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Hydrophilic mesoporous carbon nanoparticles (MCNs) have been synthesized via an extremely facile precursor carbonization-in-hot solvent route. The synthesized MCNs show well-defined particle and pore size distribution at around 100 nm and 2.7 nm, respectively, and multicolor and upconversion photoluminescence, which endow the MCNs with multicolor/upconversion bioimaging and drug delivery properties. [ABSTRACT FROM AUTHOR]

A novel hierarchical nanostructure with graphite-like carbon and small Si nanocrystals, respectively, encapsulated in the mesopores and embedded in the silica framework of mesoporous silica nanoparticles has been facilely constructed and used as an anode for Li-ion batteries, which exhibits high specific storage capacity and extraordinarily high cycling stability. [ABSTRACT FROM AUTHOR]

Zr-based MOF nanoparticles were applied as efficient carriers for alendronate delivery, and an unprecedented drug loading capacity was achieved thanks to the inherent drug anchorages of Zr--O clusters therein. The encapsulated drug featured with a pH-dependent release profile, and inhibited the growth of cancer cells more efficiently than the free drug. [ABSTRACT FROM AUTHOR]

A simple physical-vapor-infiltration (PVI) method using ferrocene as the iron source, has been developed to load FeOx into the pore channels of mesoporous silica SBA-15. The obtained FeOx/SBA-15 composite has a high loading amount of FeOx (e.g. 26.64 wt% Fe content obtained at PVI duration 17 h and calcination temperature 450°C) but unblocked pore channels thanks to the unique preparation strategy. The FeOx species are amorphous, rich of Fe2+ and have been highly dispersed as a nanocoating onto the pore channel surface. The FeOx/SBA-15 composite was used as a heterogeneous Fenton catalyst to degrade Acid orange 7 (AO7). It showed a high catalytic activity and degradation efficiency, which was attributed to the high proportion of Fe2+ in the amorphous FeOx and their favorable adsorption capability for the dye. The influences of the PVI duration, the calcination temperature and the Fenton reaction conditions (FeOx/SBA-15 dosages, H2O2 dosages and initial pH value) on the catalytic activity were investigated in detail. [ABSTRACT FROM AUTHOR]

Mesoporous Beta zeolite has been successfully prepared through hydrothermal synthesis in the presence of cationic ammonium-modified chitosan as the meso-template. Through a subsequent solid-gas reaction between highly dealuminated mesoporous Beta zeolite and SnCl4 steam at an elevated temperature, mesoporous Sn-Beta has been facilely obtained. It was revealed that the addition of cationic chitosan induced the nanocrystal aggregation to particle sizes of ~300 nm, giving rise to the intercrystalline/interparticle mesoporosity. In the Sn-implanting procedure, Sn species were demonstrated to be doped into the framework of the resulting mesoporous Beta zeolite in a tetrahedral environment without structural collapse. Due to the micro/mesoporous structures, both mesoporous Beta and Sn-Beta exhibited superior performances in a-pinene isomerization, Baeyer-Villiger oxidation of 2-adamantanone by hydrogen peroxide and the isomerization of glucose in water, respectively. [ABSTRACT FROM AUTHOR]

Mesostructured Co3O4/C composites of high surface area have been synthesized via a one-step replica route by co-nanocasting cobalt and carbon precursors into mesoporous silica, in which the Co3O4 nanoparticles are homogeneously dispersed in the mesoporous structure of carbon substrates. The mesostructured composites showed relatively high catalytic activities for oxygen reduction reaction (ORR), and that with a Co loading content of 4.3 at% exhibited the best electrochemical performance for ORR. The relatively high catalytic activity is attributed to the effects of the redox couples (Co3+/Co2+ together with the contribution from the conductive mesoporous carbon substrate. [ABSTRACT FROM AUTHOR]

Sulfur doped graphene foam has been successfully synthesized by a simple solve-thermal method, which exhibited a much enhanced oxygen reduction reaction (ORR) catalytic activity as well as an especially high electrochemical stability, and would be a promising non-metal cathode catalyst for the ORR. [ABSTRACT FROM AUTHOR]

Superparamagnetic mesoporous zeolite microspheres with a large mesopore size of 13 nm and a high surface area of 382 m² g-1 were synthesized for the capacious enrichment of proteins and enzymes. A high degree of ovalbumin immobilization was obtained (491 mg g-1) at pH 6, which is nearly twice that previously reported in the literature. [ABSTRACT FROM AUTHOR]

In this paper, a simple strategy was developed to fabricate a novel kind of uniform, biocompatible and PEGylated multifunctional hybrid micelles with multiple magnetite nanocrystal loaded cores and dye-doped silica cross-linked shells based on the self-assembly between poly(-caprolactone)-b-poly(acrylic acid) copolymer and inorganic nanoparticles. The loading of multiple magnetite nanoparticles in the core part of the hybrid micelles endows them with T2-weighted MR imaging functionalities. Small dye molecules (Rhodamine B) were directly incorporated into the silica layer framework during the cross-linking process, imparting the hybrid micelles with fluorescent imaging modality. Poly(ethylene glycol) (PEG) was grafted to reduce the phagocytic capture of nanoparticles by cellular components of the immune system. Importantly, the potential application of magnetite incorporated PEGylated hybrid micelles as T2 contrast agents for MRI was demonstrated both in vitroand in vivo, with the passive targeting behavior viaEPR effect due to the leaky vasculature and poor lymphatic drainage in tumors. [ABSTRACT FROM AUTHOR]

Here we report the presence of an unexpected fluorescence enhancement zone (E-zone) in the mechanically mixed system of superparamagnetic iron oxide nanoparticles (SPIONs) and upconversion fluorescent nanoparticles (UCNPs). This new finding differs from the traditional consideration that black SPIONs are always strong light absorbers. Our study also showed that the quenching behavior of UCNPs in the quenching zone (Q-zone) by SPIONs is surface state-dependent, with a lower quenching effect when UCNPs was shielded with a hydrophilic silica shell. [ABSTRACT FROM AUTHOR]

The biomedical applications of mesoporous silica nanoparticles (MSNs) as efficient drug delivery carriers have attracted great attention in the last decade. The structure, morphology, size, and surface properties of MSNs have been found to be facilely tunable for the purposes of drug loading, controlled drug release and delivery, and multifuctionalization. Meanwhile, the biosafety and in vivodrug efficiency of MSN-based nano drug delivery systems (nano-DDSs), involving biocompatibility (including cytotoxicity, blood and tissue compatibility) and pharmacokinetics (including biodistribution, biodegradation, retention, excretion, blood circulation) are also drawing increasing attention because of their clinical application prospects. Herein, we review the most recent research progresses on the synthesis, controlled drug release and delivery, pharmacokinetics and biocompatibility of MSNs. [ABSTRACT FROM AUTHOR]

A hierarchically porous composite with mesoporous bioactive glasses (MBG) coated on macroporous poly(l-lactic acid) (PLLA) scaffolds has been prepared through a dip-coating process of PLLA into MBG sol solution and used as an antibiotic drug carrier. Characterization of the structure and morphology of the composite scaffolds indicated a stable and homogenous MBG deposition throughout the porous framework of the scaffolds. In vitrostudies in simulated body fluid (SBF) showed great improvements of the hydrophilicity, bioactivity, and biodegradability if compared with pure PLLA scaffolds. As a result, the MBG coating promoted attachment, spreading and proliferation of rabbit bone marrow stromal cells (rBMSCs). Gentamicin sulfate (GS) was loaded into the composite system and showed a two-stage sustained release profile, which demonstrated satisfactory antibacterial properties. [ABSTRACT FROM AUTHOR]

Superparamagnetic mesoporous Mg–Fe bi-metal oxides with varied Mg–Fe atomic ratios have been successfully synthesized as solid base catalysts. The M2F-400 catalyst with Mg/Fe atomic ratio = 2 showed extraordinarily high activities for Knoevenagel reactions even at room temperature. It could be magnetically separated, recycled, and reused for at least five cycles. [ABSTRACT FROM AUTHOR]

A hierarchical micro/mesoporous aluminosilicate has been synthesized using an optimized steam-assisted crystallization method, by which the material shows perfect crystallization of zeolite frameworks and relatively high surface area and meso/micropore volumes. Key factors for the crystallization of mesoporous frameworks in the process, especially the gel drying temperature, and role of triethanolamine as mesopore template, which have not been addressed before, were identified for the successful synthesis of the hierarchical structure in detail. An energy level schematic was proposed to illustrate the role of the gel drying temperature by affecting the condensation level of the -Si–O- network in the mesoporous framework. Alteration of the experimental conditions within a certain range can yield mesoporous zeolites with varied structure properties, such as surface area, pore volume and pore size. Such hierarchical structures possess remarkably higher catalytic activity in aldol condensation reaction than both amorphous mesoporous materials and conventional ZSM-5 zeolite. [ABSTRACT FROM AUTHOR]

Highly dispersed gold nanoparticles (NPs) incorporated mesoporous titania thin films with ultrahigh Au content (53.3 wt%) were synthesized by a deposition-precipitation method using urea as precipitator, which showed high off-resonant third-order optical nonlinear susceptibility (χ(3)= 2.69 × 10−8esu) measured by the Z-scan technique at 1064 nm. The enhanced χ(3)value of the materials was attributed to the homogeneous dispersion and the ultrahigh concentration of the gold NPs, and the high linear refractive index of the titania matrix. [ABSTRACT FROM AUTHOR]

A bottom-up tailoring methodology was developed to successfully regulate the morphology and size of novel composite micellar bunches with liquid crystal mesophases self-assembled from multivalent metal ions (ZrIV) and nonionic surfactants (P123), and subsequently the morphologies and dimensions of liquid crystal-templated mesoporous silica nanomaterials (MSNs). The composite micellar bunches with liquid crystal mesophases were directly evidenced by TEM imaging and DLS measurements. By virtue of these morphologically and dimensionally controllable composite micellar bunches as templates, SBA-15 MSNs were well tailored from long nanorods of 645 × 245 nm to short nanorods of 360 × 210 nm, and even to nanoplates of 310 × 740 nm and subsphaeroidal nanoparticles of 230 nm. [ABSTRACT FROM AUTHOR]

The electronic states (HOMO/LUMO energy levels) and the electron transport characteristics of a novel AlQ3-based coordination polymer recently designed and synthesized are explored by means of cyclic voltammetry and space-charge-limited current measurements. This coordination polymer has high electron mobility, low HOMO/LUMO energy levels, high thermal stability and high solubility in ethanol and therefore can be fabricated into films by a solution process, e.g.spin coating without influencing commonly used emitter layer materials on which the electron transport layer polymer is to be deposited. All these properties and features suggest that this new coordination polymer is a very promising candidate as a high performance and low cost electron transport layer material in the application of organic light-emitting diodes. [ABSTRACT FROM AUTHOR]

Novel rhodamine B-co-condensed spherical SBA-15 nanoparticles (RhB-Cc-SBA-15NPs) and rhodamine B-post-grafted short columnar SBA-15 nanoparticles (RhB-Pg-SBA-15NPs) have been synthesized by a facile co-condensation approach and a relatively complicated post-grafting route, respectively. SEM, TEM, SAXRD, FTIR, absorption spectroscopy, fluorescence spectroscopy and nitrogen adsorption–desorption techniques were employed to characterize the morphology, the mesostructure and the spectral features of fluorescence nanocomposites with different doping amounts of RhB. The results show that (1) the facile co-condensation method involves an electron-donor–acceptor (EDA) composite micelle, which plays two significant roles of uniformly dispersing RhB groups within the ordered mesopore channels and effectively adjusting the morphology and particle size of SBA-15 in the nano-scale; (2) novel spherical RhB-Cc-SBA-15NPs with a uniform particle size of ca.400 nm have been obtained for the first time; (3) large numbers of RhB groups are covalently bound and monodisperse within the ordered mesoporous channels of the RhB-Cc-SBA-15NPs owing to the facile co-condensation method, however, most probably aggregated on the outside surface of the RhB-Pg-SBA-15NPs; (4) compared with other dye-doped silica materials reported previously, RhB-Cc-SBA-15NPs exhibit uniform size, high dispersivity and doping amounts of the bound RhB, high fluorescence quantum yields and fluorescence detectivity, and excellent photostability. RhB-Cc-SBA-15NPs, combining the advantages of a well-defined morphology and mesostructure, exhibit excellent fluorescence features, and present great potential for applications in drug delivery and fluorescence probing for medical diagnosis and synchronous therapy. [ABSTRACT FROM AUTHOR]

A well-crystallized mesoporous hydrous ruthenium dioxide (RuOxHy) with high surface area of 120 m2 g-1 and high electrochemical catalytic activity has been synthesized by a replicating route with the mesoporous silica (KIT-6) as hard template. The materials were characterized by means of thermo-gravimetric analysis (TG), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and N2 sorption. The electrocatalytic activity of the samples for methanol oxidation were investigated by cyclic voltammetry (CV) and linear scan voltammetry (LSV) techniques. A mixed gas of CO and O2 was adopted to investigate the effect of gas treatment on the electrochemical activity of the samples. The results show that the electrocatalytic activity of the prepared mesoporous RuOxHy and 3 wt% Pt/mesoporous RuOxHy toward methanol oxidation was much enhanced after treatment with a mixed gas of CO and O2. The enhanced electrochemical catalytic activity of the materials might be attributed to the structure activation during the gas treatment and the high surface area of RuOxHy matrix with mesoporous structure. [ABSTRACT FROM AUTHOR]

Au nanoparticles incorporated in mesoporous silica thin films with a high Au content 29.2 wt% were prepared, which demonstrated a higher off-resonance third-order non-linear optical susceptibility (x(3) = 8.23 x 10-10 esu). [ABSTRACT FROM AUTHOR]

A well-crystallized mesoporous hydrous ruthenium dioxide (RuOxHy) with high surface area of 120 m2g−1and high electrochemical catalytic activity has been synthesized by a replicating route with the mesoporous silica (KIT-6) as hard template. The materials were characterized by means of thermo-gravimetric analysis (TG), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and N2sorption. The electrocatalytic activity of the samples for methanol oxidation were investigated by cyclic voltammetry (CV) and linear scan voltammetry (LSV) techniques. A mixed gas of CO and O2was adopted to investigate the effect of gas treatment on the electrochemical activity of the samples. The results show that the electrocatalytic activity of the prepared mesoporous RuOxHyand 3 wt% Pt/mesoporous RuOxHytoward methanol oxidation was much enhanced after treatment with a mixed gas of CO and O2. The enhanced electrochemical catalytic activity of the materials might be attributed to the structure activation during the gas treatment and the high surface area of RuOxHymatrix with mesoporous structure. [ABSTRACT FROM AUTHOR]

An amorphous silica hybrid film containing covalently linked azobenzene chromophores and Ag nanoparticles was synthesized by a one-step sol-gel route in the presence of amino trialkoxysilane (APTES). The electron transfer from the N-containing groups in the APTES and azobenzene molecules, which are chemisorbed onto the surface of Ag nanoaprticles, makes the Ag nanoparticles negatively charged. Subsequently, a new D–π–A electron structure between the Ag nanoparticles and the N-containing groups/azobenzene chromophores is created. The enhanced internal electric field in the nanoparticles and the strengthened and extended π-conjugation in the new D–π–A electron structure, lead to the large enhancement of optical non-linearity of the hybrid films. [ABSTRACT FROM AUTHOR]

A mesoporous tungsten carbide (WC) with high surface area (138 m2g−1) has been synthesized at 700 °C using a modified template replicating route in which the pore entrances were sealed under external pressure after the W source impregnation. X-Ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) spectroscopy and nitrogen sorption techniques were employed to characterize the replicated material. The prepared tungsten carbide with high surface area is well crystallized and has a partially ordered mesoporous structure. Temperature programmed reaction (TPR) and time-on-stream (TOS) results show that the prepared mesoporous tungsten carbide has high and stable catalytic activity for the decomposition reaction of NH3, and the complete NH3decomposition temperature was obtained at 500 °C. This mesoporous WC appears to be a good catalyst for use for NH3decomposition. [ABSTRACT FROM AUTHOR]

Mesoporous CaO–MO–SiO2–P2O5 (M = Mg, Zn, Cu) bioactive glasses/composites have been prepared by a one-pot synthesis route of simultaneous evaporation-induced self-assembly of Ca, P, Si and M sources. The effects of the substitution of CaO by MO in the mesoporous bioactive glasses/composites on the mesoporous structure and hydroxyapatite (HA)-forming ability were studied. The amorphous silicate can be detected on all the mesoporous CaO–MO–SiO2–P2O5 (M = Mg, Zn, Cu) bioactive glasses/composites, and Zn2SiO4 and CuO can be clearly detected on bioactive glass with high Zn contents and all of the Cu-containing bioactive glasses/composites, respectively. The MgO-substituted bioactive glasses/composites show the highest surface area among all MO-containing glasses/composites and the presence of crystallized phases of Zn2SiO4 and CuO in the ZnO- and CuO-containing bioactive glasses/composites lead to the decreased surface area and pore volume. The substitution of Ca with Mg, Zn or Cu inhibits the formation of HA deposition on the surface of the mesoporous bioactive glasses/composites, especially at high MO contents. The presence of MgO, ZnO and CuO slowed down the deposition rate of HA following a sequence of Cu < Mg < Zn. Therefore, the HA crystallite size and morphology can be easily tuned by the incorporation of Mg, Zn and Cu, which facilitates the wide application of the mesoporous bioactive glasses/composites. [ABSTRACT FROM AUTHOR]

A new soluble tris(8-hydroxyquinoline) aluminium (AlQ3)-based coordination polymer named CP-B8QBA-Al has been synthesized. In contrast with the traditional coordination polymers, this new coordination polymer CP-B8QBA-Al does not crystallize and can be fabricated into amorphous films by conventional spin-coating. The third-order nonlinear optical properties of the CP-B8QBA-Al films were investigated using the Z-scan method at 800 nm and 1064 nm, the results show the coordination polymer films have a third-order NLO susceptibility χ(3) value as high as 1.66 × 10−10 esu without nonlinear absorption. [ABSTRACT FROM AUTHOR]

Chemically active isocyanurate-bridged periodic mesoporous organosilica materials with high loadings of pendant thiol groups have been synthesized via co-condensation under acidic conditions, using the triblock copolymer EO20PO70EO20 (P123) as template and a mixture of mercaptopropyl-containing silane and isocyanurate-containing silsesquioxane to form the framework. The obtained SH–ICS–PMOs were characterized by XRD, transmission electron microscopy (TEM), solid state 13C and 29Si MAS NMR spectroscopy, and N2 physical sorption. The data show that well-ordered SH–ICS–PMOs were obtained with 40% of the framework Si atoms bearing the thiol pendant groups. Interestingly, the introduction of the thiol groups improved the mesostructural ordering and favored the cross-linking of the pore walls. The determination of Hg2+ uptake from aqueous solution as a test case showed that both the bridging ICS groups and the pendant thiol groups in the SH–ICS–PMOs are active in adsorbing Hg2+. Our study demonstrated that well-ordered periodic mesoporous organosilicas are capable of supporting both chemically active bridging groups and active pendant groups with high loadings. [ABSTRACT FROM AUTHOR]

The Bi-based oxychloride Bi4NbO8Cl with a layered structure was studied as a novel efficient photocatalyst. The compound prepared by a solid state reaction method has a band gap of 2.38 eV. It possesses an excellent visible-light-response ability. The visible-light-driven photocatalytic activities for degrading methyl orange (MO) over different catalysts follow the decreasing order of Bi4NbO8Cl > Bi3O4Cl > anatase TiO2, different from the order found under UV light illumination (Bi3O4Cl > anatase TiO2 > Bi4NbO8Cl). The dispersion of Pt over Bi4NbO8Cl leads to an obvious increase in photocatalytic performance, to about 1.5 times higher. The polarizing fields in NbO6 and BiO8 local structures, as well as the internal electrical fields between [Bi2O2] and [Cl] slabs, are considered to be useful for the efficient separation of electron–hole pairs upon photoexcitation. [ABSTRACT FROM AUTHOR]

A simple approach has been developed to synthesize hierarchically porous MnO2 with a crystalline nanorod framework using mesoporous silica SBA-15 as a template, combined with in situ ion-exchange and surfactant-extraction processes without calcination. XRD, nitrogen adsorption analysis, FE-SEM, TEM, XPS and FT-IR techniques are used for the structural characterization. Such MnO2 materials show a macro–mesoporous hierarchical nanostructure containing large pores of several hundreds of nanometres and mesopores of 3.76 nm with a high surface area of 142 m2 g−1. The mesoporous framework of this material is composed of aligned single crystalline MnO2 nanorods of ca. 5–6 nm in diameter and ca. 20–25 nm in length. The electrochemical properties of the prepared MnO2 material were studied using cyclic voltammetry in a mild aqueous electrolyte, which shows that such a MnO2 nanostructure has a very high specific capacitance of 258 F g−1 and a good reversibility due to its favorable phase and hierarchically porous structure as well as high surface area. [ABSTRACT FROM AUTHOR]

We report the synthesis of a new kind of uniform hollow zeolite microspheres with hierarchical macro-/meso-/microporosity by an efficient strategy combining bi-templating, steam-assisted crystallization and then a mild alkaline etching method. This novel product has a hollow architecture, highly crystallized zeolite shells and more importantly, high dye adsorption capabilities. [ABSTRACT FROM AUTHOR]

A mesoporous silica nanoparticle (MSN)-based pH-responsive nano drug delivery system (hydrophobic drugs@micelles@MSNs) is constructed by a one-pot self-assembly strategy, exhibiting improved drug efficacy against both drug-resistant and drug-sensitive cancer cells. [ABSTRACT FROM AUTHOR]

We report the design and chemical synthesis of covalently bonded azomethin–zinc/SiO2hybrid transparent thin films with photoluminescent and electroluminescent emissions in condensed solid state by a sol-gel approach. [ABSTRACT FROM AUTHOR]

We report the direct fabrication of mesoporous zeolite with a hollow spherical/ellipsoidal capsule structure by using conventional TPAOH and CTAB as soft micro- and mesopore generating templates; the mesoporous zeolite shows a high surface area of 717 m2 g-1 and small mesopore size of around 3 nm. [ABSTRACT FROM AUTHOR]

Mesoporous microspheres of zeolite have been fabricated through direct self-assembly between an aluminosilicate precursor, tetrapropylammonium hydroxide (TPAOH) and poly(methyl methacrylate) (PMMA) nanospheres, where the PMMA nanospheres act as dual-functional templates for the generation of both mesoporosity and spherical morphology. [ABSTRACT FROM AUTHOR]

Hollow mesoporous carbon spheres (HMCSs) were used for the first time as a bilirubin adsorbent, which showed an extraordinarily high bilirubin adsorption capacity as compared with commercial activated carbon for haemoperfusion, high bilirubin adsorption selectivity and negligable hemolytic activity. The results are very attractive and promising for blood purification applications. [ABSTRACT FROM AUTHOR]

Novel amino- or thiol-functionalized superparamagnetic copolymer-silica nanospheres (NH2-SMCSNs/SH-SMCSNs), which consist of a magnetic core and a silica cross-linked block copolymer shell, have been fabricated. [ABSTRACT FROM AUTHOR]

Hollow mesoporous silica nanospheres (HMSNs) with tunable sizes of both sphere diameter (around 100 nm) and shell thickness have been successfully fabricated. [ABSTRACT FROM AUTHOR]

Mg-Al layered double hydroxide (LDH) nanocrystallites with a lateral size less than 9 nm were in situ synthesized within the pore channels of mesoporous silica materials, creating one of the most active heterogeneous base catalysts owing to the high number of active edge sites. [ABSTRACT FROM AUTHOR]