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We present a one-pot method for the encapsulation of small Ni particles into a dendritic SiO2 skeleton. Such confined Ni particles are robust against metal particle sintering and preferentially grow amorphous carbon instead of graphitized carbon, which maintain high activity and stability towards methane dry reforming at 700 °C for 200 h. [ABSTRACT FROM AUTHOR]

We report an integrated production of bio-jet fuel, from dehydrogenation of lignin-derived cycloalkanes and deoxygenation of lipid over PtIr/γ-Al2O3 at 400 °C in the absence of hydrogen. The CO generated in situ via lipid decarbonylation is strongly adsorbed by Ir and subsequently undergoes methanation, with the remaining Pt sites catalyzing cycloalkane dehydrogenation. [ABSTRACT FROM AUTHOR]

We report a new hydrothermal and basic-additive free process for synthesizing a core(single-crystalline HBEA zeolite)–echinus(nickel phyllosilicate) catalyst, which exhibits excellent reactivity and stability for hydrogenation reactions. Desilication and dealumination processes generate substantial SiO32− ions and exposed Si–OH groups to form nickel phyllosilicate on the external and internal surfaces of zeolite. [ABSTRACT FROM AUTHOR]

Hierarchically porous zeolite supported metal nanoparticles are successfully prepared through a base-assisted chemoselective interaction between the silicon species on the zeolite crystal surface and metal salts, in which in situ construction of mesopores and high dispersion of metal species are realized simultaneously. [ABSTRACT FROM AUTHOR]

Reactions of lanthanide nitrate, 1,3,5-benzenetrisbenzoic acid (H3BTB) and [RMI]Br ionic liquids (RMI = 1-alkyl-3-methylimidazolium; R = ethyl, propyl, butyl, amyl, or hexyl), gave rise to two novel lanthanide metal–organic frameworks (Ln-MOFs) [Ln(BTB)H2O], where Ln = Eu 1, Tb 2. In addition to helping solubilise the starting materials under the reaction conditions there is evidence that [RMI]Br itself can play a structure directing role and is intimately involved in template ordering in [Ln(BTB)H2O], even though neither the [RMI]+ cation nor the Br− anion is occluded into the ultimate structure. 1 and 2 are isostructural and consist of infinite rod-shaped lanthanide-carboxylate building units which are further bridged by trigonal-planar BTB ligands to give noninterpenetrated open 3D frameworks featuring a (6,6)-connected topology with the point symbol (44·67·84)(48·67). Importantly, the strong emission of 1 and 2 dispersed in water prompted us to explore their application for detection of different nitroaromatics in an aquatic system. 1 and 2 show similar selectivity and sensitivity towards the presence of trace amounts of nitroaromatic analytes in the aqueous phase, showing potential as explosive sensors. [ABSTRACT FROM AUTHOR]

The ability to construct supported metal catalysts with high dispersion at high metal loadings is of crucial importance. There are two great challenges to be overcome in order to achieve this goal: the issue of stability of the support material with high surface areas and abundant mesopores at working conditions, and the issue of metal nanoparticles agglomeration upon harsh treatments, especially for transition metals that are difficult to reduce and aggregate easily. To overcome these problems, here we propose a new and promising strategy for encapsulating the Ni nanoclusters (d = 5.6 nm) into/onto the uniform and inter-connected intra-mesopores (7–8 nm) of single-crystalline HBEA, achieving highly dispersive Ni nanoparticles (content: 40 wt%, dispersion: 3.5%) on the stable carrier. The architecture of relative position of the Ni nanoparticles and support is directly revealed by ultrathin sections transmission electron microscopy and N2 sorption measurements, presented together with the indirect evidences of temperature programmed reduction of H2 and IR spectroscopy of adsorbed CO. In comparison to such an advantageous structure of metal and support, the Ni nanoparticles are more commonly deposited on the limited external surface or inter-mesopores of commercial HBEA carriers. Besides, the novel catalyst shows superior adsorption performance towards large molecules. As expected, the catalyst leads to a significantly high initial rate of 132 mmol g−1 h−1 (equivalent to 38 g g−1 h−1) and highly selective octadecane formation (96% yield) from stearic acid conversion. Consequently, high activity and stable durability are realized for four recycling runs of drainage oil hydrodeoxygenation with the newly developed Ni/HBEA. [ABSTRACT FROM AUTHOR]

The NHC-stabilized silylaminosilylene Ar(SiMe3)N(Cl)Si(IiPr) (1, Ar = 2,6-iPr2C6H3, IiPr = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene) reacted rapidly with a series of enolizable ketones under ambient conditions in a stereo- and regioselective fashion to afford silicon bis-enolates (2a–o) in high yields with the elimination of imidazolium salt. In contrast, reaction of 1 with two equivalents of benzophenone led to a slow bis-silylation of the C=O double bond. All of the products have been characterized by 1H, 13C, and 29Si NMR spectroscopy and HR-MS analysis. The configurations of compounds 2h–n were determined by NOESY experiments. [ABSTRACT FROM AUTHOR]

A highly active catalyst, hierarchical nano-sized Ni/HBEA, is developed for stearic acid and palm oil hydrodeoxygenation (HDO) in dodecane. The TPAOH/NaOH treated hierarchical HBEA sample (crystal size: 15–20 nm) affords more homogeneously dispersed open inter-mesopores (main pore diameter: 25 nm) via controllable base leaching, as evidenced by various microscopy and spectroscopy techniques. By the formation of an aluminum complex on the crystal surface, TPA+ prevents the specific external structure from deep corrosion. After loading Ni nanoclusters, the modified Ni/HBEA was supported with more loadable and dispersive Ni nanoclusters (d = 7.7 ± 1.5 nm) in the newly formed inter-crystalline mesopores, which provide higher accessibility towards heavy molecules, as well as restrict the Ni particle growth. This novel catalyst shows a significantly high initial rate of 67 mmol g−1 h−1 (equivalent to 19 g g−1 h−1) for producing 85% n-C17/C18 and 11% iso-C17/C18 alkanes by stearic acid conversion at 260 °C and 4 MPa H2, and the efficiency of this method is far beyond the current techniques using sulfur-metal and reduced-metal catalysts. The HDO route follows the major pathway of sequential hydrogenation and dehydration steps, affording a highly atom-economical process and a suitable diesel oil ingredient (with certain branched alkanes). In addition, high activities are achieved with the improved catalyst after treatment with high concentration stearic acid in dodecane (up to 0.5 g mL−1), and the catalyst remains highly active and stable in the four recycling runs of palm oil HDO. [ABSTRACT FROM AUTHOR]

In this study, a series of phenyl β-aldehyde ketones were designed and synthesized as novel dual inhibitors of aldose reductase (ALR2) and α-glucosidase. The results showed substantial inhibition of ALR2 and α-glucosidase by the synthetic compounds and also demonstrated the antioxidant activity of these inhibitors. Among them, compound 5l had the most potent inhibitory effect on both enzymes, with non-competitive inhibition patterns, and was the most effective antioxidant in tests for 2,2-diphenyl-1-picrylhydrazyl radical scavenging and lipid peroxidation suppression. High lipophilicity and negligible cytotoxicity were also observed for this compound. Analysis indicated that the β-aldehyde ketone moiety might play a vital role in the inhibitory effect on the enzymes and that the phenolic hydroxy group was the key structure for intensifying the inhibitory and antioxidant activities. Overall, the results confirmed the successful synthesis of potent ALR2 and α-glucosidase inhibitors with antioxidant activity. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) films are deposited on flexible Kapton substrates and selectively modified to conductive reduced graphene oxide (rGO) electrodes using laser patterning. Based on this, we design, fabricate, and test a flexible sensor integrating laser-reduced GO with silver plasmonic nanostructures. The fabricated device results in dual transduction channels: for electrochemical and plasmonic nanostructure-based surface-enhanced Raman spectroscopy (SERS) detection. The spectroscopic analysis verifying the formation of rGO and the modification by silver nanostructures is performed by Raman, energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). The morphological investigation is followed by optical and scanning electron microscopy imaging. In addition to pristine silver nanostructures, the Raman spectroscopy results show the formation of species such as Ag2O, Ag2CO3, and Ag2SOx. A dual-channel sensor device based on electrochemical and plasmonic detection is fabricated as a demonstration of our Ag–rGO flexible concept architecture. The dual-channel device performance is successfully demonstrated in the electrochemical and SERS detection of 4-nitrobenzenethiol (4-NBT) using the same device. Our results show that without Ag nanostructures the sensitivity in the electrochemical and optical channels is not sufficient to detect 4-NBT. The performance and stability of the silver modified device are also verified. This work demonstrates an inexpensive, highly efficient, and greener way that is compatible with solution-processing technology for the production of flexible GO-based electrochemical and SERS detection devices integrated with plasmonic nanostructures. [ABSTRACT FROM AUTHOR]

Rechargeable lithium-ion batteries (LIBs) are important electrochemical energy storage devices for consumer electronics and emerging electrical/hybrid vehicles. However, one of the formidable challenges is to develop ultrafast charging LIBs with the rate capability at least one order of magnitude (＞10 C) higher than that of the currently commercialized LIBs. This tutorial review presents the state-of-the-art developments in ultrafast charging LIBs by the rational design of materials. First of all, fundamental electrochemistry and related ionic/electronic conduction theories identify that the rate capability of LIBs is kinetically limited by the sluggish solid-state diffusion process in electrode materials. Then, several aspects of the intrinsic materials, materials engineering and processing, and electrode materials architecture design towards maximizing both ionic and electronic conductivity in the electrode with a short diffusion length are deliberated. Finally, the future trends and perspectives for the ultrafast rechargeable LIBs are discussed. Continuous rapid progress in this area is essential and urgent to endow LIBs with ultrafast charging capability to meet huge demands in the near future. [ABSTRACT FROM AUTHOR]

A colorimetric logic gate based on free gold nanoparticles is presented with melamine and Hg2+, as well as its colorimetric detection of Hg2+ with good selectivity and sensitivity. [ABSTRACT FROM AUTHOR]