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Supported gold nanoparticles are emerging catalysts for heterogeneous catalytic reactions, including selective hydrogenation. The traditionally used supports such as silica do not favor the heterolytic dissociation of hydrogen on the surface of gold, thus limiting its hydrogenation activity. Here we use gold catalyst particles partially embedded in the pore walls of mesoporous carbon with carbon atoms occupying interstitial sites in the gold lattice. This catalyst allows improved electron transfer from carbon to gold and, when used for the chemoselective hydrogenation of 3-nitrostyrene, gives a three times higher turn-over frequency (TOF) than that for the well-established Au/TiO 2 system. The d electron gain of Au is linearly related to the activation entropy and TOF. The catalyst is stable, and can be recycled ten times with negligible loss of both reaction rate and overall conversion. This strategy paves the way for optimizing noble metal catalysts to give an enhanced hydrogenation catalytic performance.

Na-ion batteries (NIBs) have attracted considerable attention in recent years owing to the high abundance and low cost of Na. It is well known that S doping can improve the electrochemical performance of carbon materials for NIBs. However, the current methods for S doping in carbons normally involve toxic precursors or rigorous conditions. In this work, we report a creative and facile strategy for preparing S-doped porous carbons (SCs) via the pyrolysis of conjugated microporous polymers (CMPs). Briefly, thiophene-based CMPs served as the precursors and doping sources simultaneously. Simple direct carbonization of CMPs produced S-doped carbon materials with highly porous structures. When used as an anode for NIBs, the SCs exhibited a high reversible capacity of 440 mAh g -1 at 50 mA g -1 after 100 cycles, superior rate capability, and excellent cycling stability (297 mAh g -1 after 1000 cycles at 500 mA g -1 ), outperforming most S-doped carbon materials reported thus far. The excellent performance of the SCs is attributed to the expanded lattice distance after S doping. Furthermore, we employed ex situ X-ray photoelectron spectroscopy to investigate the electrochemical reaction mechanism of the SCs during sodiation-desodiation, which can highlight the role of doped S for Na-ion storage.

Being an important I-III-VI green quantum dot (QD), AgInS 2 (AIS) has been used as sensitizers for QD sensitized solar cells (QDSCs) but with low power conversion efficiency (PCE). Herein, we have used oleylamine as surfactant to synthesize AIS and quaternary Zn-Ag-In-S (ZAIS) QDs via a facile and green method. The assembled AIS QDSCs show high PCE of 2.46%. After doping with Zn to form ZAIS QDs, the defect states have been modified, resulting in the enhanced photoluminescence. The assembled ZAIS QDSCs receive the greatly enhanced PCE of 4.50% with dramatically increased current density. Various characterizations verify that the high quality of QDs, large recombination resistance at QD/electrolyte interface, high photon to electron conversion efficiency and longer electron life are contributed by the tuned intrinsic defects which are strongly related with synthesis and composition, finally leading to the high performance of photovoltaic devices., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Next-generation sequencing studies have reported that rare variants in PLD3 were associated with increased risk of late-onset Alzheimer's disease (LOAD) in European cohorts. The association has been replicated in a Han Chinese cohort, two rare variants p.I163M in exon7 and p.R356H in exon11 of PLD3 were found to be associated with LOAD risk. Whether these variants have deleterious effects on protein function, and the underlying mechanisms by which they influence LOAD pathogenesis are unknown. Our results are the first to validate the hypothesis that these variants could lead to reduced PLD3 activity and affect amyloid-β levels in cellular model of AD, possibly via autophagy-dependent mTOR signaling pathway, indicating that PLD3 may represent a new therapeutic target for AD.

Interfacial nanostructures in Bi2S3-TiO2 nanorod-nanoparticle heterostructures with a change of coupling mode have been engineered. The samples were characterized by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, and ultraviolet-visual light absorption spectroscopy. By means of in situ growth of TiO2 nanoparticles on the surfaces of Bi2S3 nanorods in one pot, heterostructures with high-quality interfaces were obtained in which the {105} facet of anatase TiO2 selectively coupled with the {010} facet of orthorhombic Bi2S3 nanorods without any crystal defects, showing the epitaxial relationship of Bi2S3 {011} // TiO2 {101}. By means of a two-step method, TiO2 nanoparticles also could be grown on the {310} facet of the pre-prepared Bi2S3 nanorods to form heterostructures but with interfacial defects. Charge transfer in the interface-different heterostructures was evaluated by photodegradation of methyl orange under visible-light irradiation. The defect-free interfaces favored electron-hole separation and transfer, resulting in improved photocatalytic activity. The current structural characterization and interface engineering should be expanded to other heterostructures when studying the relationship between synthesis, interfacial structure, and photocatalytic or photovoltaic applications.

A coordination-assisted synthetic approach is reported here for the synthesis of highly active and stable gold nanoparticle catalysts in ordered mesoporous carbon materials using triblock copolymer F127 as a structure-directing agent, thiol-containing silane as a coordination agent, HAuCl4 as a gold source, and phenolic resin as a carbon source. Upon carbonization, the gold precursor becomes reduced to form monodispersed Au nanoparticles of ca. 9.0 nm, which are entrapped or confined by the "rigid" mesoporous carbonaceous framework. Nanoparticle aggregation is inhibited even at a high temperature of 600 °C. After removal of the silica component, the materials possess the ordered mesostructure, high surface area (~1800 m(2)/g), large pore volume (~1.19 cm(3)/g), and uniform bimodal mesopore size (<2.0 and 4.0 nm). The monodispersed gold nanoparticles are highly exposed because of the interpenetrated bimodal pores in the carbon framework, which exhibit excellent catalytic performance. A completely selective conversion of benzyl alcohol in water to benzoic acid can be achieved at 90 °C and 1 MPa oxygen. Benzyl alcohol can also be quantitatively converted to benzoic acid at 60 °C even under an atmospheric pressure, showing great advantages in green chemistry. The catalysts are stable, poison resistant, and reusable with little activity loss due to metal leaching. The silane coupling agent played several functions in this approach: (1) coordinating with gold species by the thiol group to benefit formation of monodispersed Au nanoparticles; (2) reacting with phenolic resins by silanol groups to form relatively "rigid" composite framework; (3) pore-forming agent to generate secondary pores in carbon pore walls, which lead to higher surface area, larger pore volumes, and higher accessibility to to the gold nanoparticles. Complete removal of the silica component proves to have little effect on the catalytic performance of entrapped Au nanoparticles.

Ordered mesoporous Al2O3-SiO2-carbon nanocomposites have been synthesized via the direct triblock-copolymer self-assembly route using soluble phenolic resols as polymer precursors, aluminium chloride hexahydrate as an aluminum precursor, tetraethoxysilane as a silica precursor, and Pluronic F127 as a template. Characterization of XRD, N2 sorption isotherms, TEM, solid-state NMR, TG, and NH3-TPD techniques is used to investigate the mesostructure, pore properties, phase composition, metal incorporation state, and acidic properties. Ordered mesoporous nanocomposites have "reinforced concrete"-structured frameworks, in which the oxide and carbon components are microphase separated and homogenously dispersed inside pore walls. Al species are tetrahedrally incorporated into silica frameworks to compose the inorganic oxide compounds which provides acidic center. The nanocomposites have the ordered 2-D hexagonal mesostructure, high surface areas (291-360 m2/g), large pore volumes (0.25-0.42 cm3/g), large pore diameters (- 5 nm) and accessible acidic sites.

An improvement in the photodegradation performance for dyes due to interaction between carbon and titania in a self-assembled mesoporous C-TiO(2) composite catalyst, even for the difficult degradation of azo dyes, is reported herein. The dye removal process involves adsorption of the dye from water by the mesoporous carbon-titania, followed by photodegradation on the separated dye-loaded solid. Such adsorption-catalysis cycles can be carried out more than 80 times without discernible loss of photocatalytic activity or the anatase content of the composite. In each run, about 120 mg dye per g catalyst can be degraded. The mesoporous carbon-titania catalyst also exhibits a high capacity for converting methyl orange in aqueous solution under visible light. Characterization by XRD, TEM, and N(2) sorption techniques has revealed that the self-assembled composite catalyst has an ordered mesostructure, uniform mesopores (4.3 nm), a large pore volume (0.30 cm(3) g(-1)), and a high surface area (348 m(2) g(-1)). The pore walls are composed of amorphous carbon and anatase nanoparticles of size 4.2 nm, which are well dispersed and confined. X-ray photoelectron spectroscopy (XPS), surface photovoltage spectroscopy (SPS), and UV/Vis absorption results indicate doping of carbon into the anatase lattice and a change in the bandgap of the semiconductor. The synergistic improvement in the composite catalyst can be attributed to the following features: (1) carbon doping of the anatase lattice modifies its bandgap and enhances its activity under visible light; (2) confinement within carbon pore walls prevents aggregation of tiny anatase nanoparticles, improving their activity and stability; (3) the mesopores provide a confined space for photocatalysis; and (4) the strong adsorption ability of porous carbon for organic substances ensures that large quantities can be processed and inhibits further diffusion of the adsorbed organic substances, thereby enhancing the mineralization on anatase., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

CdSe quantum dot (QD ) sensitized TiO(2) films have been fabricated using a one-step microwave assisted chemical bath deposition (MACBD) technique and used as photoanodes for quantum dot sensitized solar cells. This technique allows direct and rapid deposition and a good contact between the CdSe and TiO(2) films. The photovoltaic performances of the cells with CdSe deposited at different times are investigated. The results show that cells based on MACBD deposited TiO(2)/CdSe electrodes achieve a maximum short circuit current density of 12.1 mA cm(-2) and a power conversion efficiency of 1.75% at one Sun (AM 1.5 G, 100 mW cm(-2)), which is comparable with those fabricated using conventional techniques., (© The Royal Society of Chemistry 2011)

Hierarchical Cu4V2.15O9.38 micro-/nanostructures have been prepared by a facile "forced hydrolysis" method, from an aqueous peroxovanadate and cupric nitrate solution in the presence of urea. The hierarchical architectures with diameters of 10-20 µm are assembled from flexible nanosheets and rigid nanoplates with widths of 2-4 µm and lengths of 5-10 µm in a radiative way. The preliminary electrochemical properties of Cu4V2.15O9.38 have been investigated for the first time and correlated with its structure. This material delivers a large discharge capacity of 471 mA h g(-1) above 1.5 V, thus making it an interesting electrode material for primary lithium ion batteries used in implantable cardioverter defibrillators.

Quantum dot-sensitized solar cells based on Zn-doped TiO(2) (Zn-TiO(2)) film photoanode and polysulfide electrolyte were fabricated. Zn-TiO(2) nanoparticles were obtained via a hydrothermal method and screen printed on the fluorine-doped tin oxide glass to prepare the photoanode. The structure, morphology and impedance of the Zn-TiO(2)/CdS film and the photovoltaic performance of the Zn-TiO(2)/CdS cell were investigated. It was found that the photovoltaic efficiency was improved by 24% when the Zn-TiO(2) film was adopted as the photoanode of CdS QDSSCs instead of only the TiO(2) layer. The improvement was ascribed to the reduction of electron recombination and the enhancement of electron transport in the TiO(2) film by Zn doping.

Ni-B nanospheres were synthesized through chemical reduction of nickel ions with borohydride in an emulsion system comprised of cyclohexylamine, polyethylene glycol, and water. With the characterization of X-ray diffraction, selective area electronic diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy, the resulting hollow Ni-B nanospheres were identified to be amorphous alloys with a hollow chamber. Cyclohexylamine played a significant role in fabricating hollow Ni-B nanospheres, because only solid nanoparticles were obtained in the absence of cyclohexylamine. Polyethylene glycol also had a significant influence on the formation of hollow Ni-B nanospheres, because low yield of hollow nanospheres were achieved without this polymer. During liquid-phase chloronitrobenzene hydrogenation, the as-synthesized Ni-B catalyst exhibited a much higher activity and even better selectivity than the dense Ni-B nanoparticles prepared by direct reduction of nickel ions with borohydride.

Heterogeneous palladium catalysts, which are supported on ordered mesoporous silica-carbon nanocomposites, have been applied in water-mediated coupling reactions of chlorobenzene without assistance of any phase-transfer catalysts. Characterization by XRD, TEM, N(2) sorption, FT-IR, TG, XPS, and H(2) chemisorption techniques reveals the highly ordered mesostructure, high surface areas (approximately 345 m(2)/g), large pore volumes (approximately 0.46 cm(3)/g), uniform mesopore sizes (approximately 6.3 nm), hybrid silicate and carbonaceous compositions, and a high dispersion of palladium nanoparticles (about 3 nm) in the mesopores. The catalyst exhibits a high yield for trans-stilbene (approximately 60%) in the Heck coupling reaction of chlorobenzene and styrene at 100 degrees C and for biphenyl (46%) in the Ullmann coupling reaction of chlorobenzene at 30 degrees C, using water as a solvent. When substituted aryl chlorides (hydroxyl, methoxyl, and methyl) are involved in the Ullmann reaction, the yields of symmetrical substituted biphenyl are also higher than 44% (this value reaches 86% for the coupling reaction of 4-chlorophenol) at a low temperature of 30 degrees C. This heterogeneous catalyst is stable, which shows negligible metal leaching, and can be reused more than 20 times. For comparison, the catalytic activities for Pd catalysts supported on pure mesoporous polymeric, carbonaceous, and silicate frameworks are also investigated. The results clearly indicate that the pore wall nature shows great influence on the dispersion of metallic Pd species and, in turn, the catalytic performance.