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The spectacular success in materials science of the application of combinatorial chemistry has raised the hope that it may eventually lead to a new scientific approach to catalyst development. This method is, within the constraints of heterogeneous catalysis, merely a potentially efficient tool to be used in rational catalyst development and should not be considered an independent novel strategy towards rational catalyst design.  相似文献   

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Carbon dots (CDs) are emerging as a new class of carbon nanomaterials, which have inspired growing interest for their widespread applications in anti-counterfeiting, sensing, bioimaging, optoelectronic and energy-related fields. In terms of the concept of host–guest assembly, immobilizing CDs into porous materials (PMs) has proven to be an effective strategy to avoid the aggregation of bare CDs in solid state, in particular, the host—guest synergy with both merits of CDs and PMs affords composites promising properties in afterglow and tunable emissions, as well as optimizes their performance in optics, catalysis, and energy storage. This Minireview summarizes the recent progress in the research of CDs@PMs, and highlights synthetic strategies of constructing composites and roles of porous matrices in boosting the applications of CDs in diverse areas. The prospect of future exploration and challenges are proposed for designing advanced CDs-based functional nanocomposite materials.  相似文献   

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Carbon nanotubes used for constructing biosensor was described for the first time. Single-wall carbon nanotubes (SWNTs) functionalized with carboxylic acid groups were used to immobilize glucose oxidase forming a glucose biosensor. The biosensor response can be determined by amperometric method at a low applied potential (0.40V).  相似文献   

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Single-walled Carbon Nanotubes as Electrode Materials for Supercapacitors   总被引:2,自引:0,他引:2  
Large-scale synthesized single-walled carbon nanotubes (SWNT) prepared by electric arc discharge method and a mixture of NiO and Y2O3 as catalyst have been used as electrode materials for supercapacitors. N2 adsorption/desorption measurement shows that the SWNT is a microporous and mesoporous material with specific surface area 435 m^2·g^-1. The specific capacitance of the nitric acid treated SWNT in aqueous electrolyte reaches as high as 105 F/g, which is a combination of electric double layer capacitance and pseudocapacitance. The SWNT-based capacitors also have good charge/discharge reversibility and cycling perdurability.  相似文献   

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s: Oxide-supported metal catalysts, having always nano-sized structures in which the metal catalysts are prepared as highly dispersed nano-crystals (typically 1-20 nm) on support oxide particles that are often one to several orders of magnitude larger than the metal nano-particles, are an important class of heterogeneous metal catalysts that finds many applications in chemical/petrochemical industries, in environmental protection, in chemical sensors and in the manufacture of fine and special c…  相似文献   

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Ab initio and DFT calculations are used to investigate the structure, electronic properties, spectra and reactivity of cubic C8, which is predicted to be aromatic according to Hirsch′s rule. Although highly strained and with a small amount of diradical character, the carbon cube represents a surprisingly deep minimum and should therefore be observable as an isolated molecule. It is, however, predicted to be very reactive, both with itself and triplet oxygen. Calculated IR, Raman, and UV/Vis spectra are provided to aid identification of cubic C8 should it be synthesized.  相似文献   

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Intriguing properties and functions are expected to implant into metal–organic layers (MOLs) to achieve tailored pore environments and multiple functionalities owing to the synergies among multiple components. Herein, we demonstrate a facile one-pot synthetic strategy to incorporate multiple functionalities into stable zirconium MOLs via secondary ligand pillaring. Through the combination of Zr6-BTB (BTB=benzene-1,3,5-tribenzoate) layers and diverse secondary ligands (including ditopic and tetratopic linkers), 31 MOFs with multi-functionalities were systematically prepared. Notably, a metal–phthalocyanine fragment was successfully incorporated into this Zr-MOL system, giving rise to an ideal platform for the selective oxidation of anthracene. The organic functionalization of two-dimensional MOLs can generate tunable porous structures and environments, which may facilitate the excellent catalytic performance of as-synthesized materials.  相似文献   

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S ee ing into the future : A range of computational methods have been applied to harmonize predicted ee values with experimental values. Novel ways of combining quantum mechanics and molecular mechanics feature prominently.

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Carbonmonoxide(CO)witholefinscanbec0p0lymerizedwithfreeradicalinitiatorsorn0bletransitionmetalc0mpoundcatalystS.Thefreeradicalinitiatedcopolymerizationunderhighgaspressure(upt0l(X)Mpa)andl2O-l65oC',whereasthemostusednobletransitionmetalcompoundsf0rthec0polymerizati0nofcarbonmonoxidewitholefinsarepalladiumorrhodiumcompounds"'.In0urw0rk,theneodymiumcomp0undcatalystsystemswerefoundt0beactiveforthecopolymerizationofstyreneandcarbonm0noxide.Thecopolymerizationofstyreneandcarbonm0n0xidewascAned0u…  相似文献   

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Noncovalent interactions are an integral part of the modern catalysis toolbox. Although stronger noncovalent interactions such as hydrogen bonding are commonly the main driving force of catalysis, π–π interactions typically provide smaller additional stabilizations, for example, to afford selectivity enhancements. Here, it is shown computationally that pristine graphene flakes may efficiently catalyze the skeletal inversions of various benzannulated cyclooctatetraene derivatives, providing an example of a catalytic process driven solely by π–π stacking interactions. Hereby, the catalytic effect results from disproportionate shape complementarity between catalyst and transition structure compared with catalyst and reactant. An energy decomposition analysis reveals electrostatic and, especially with increasing system size, to a larger extent, dispersion interactions as the origin of stabilization.  相似文献   

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Titanium-containing mesoporous molecular sieves are of great significance in selective catalytic oxidation processes with bulky molecules. Recent researches and developments on the designing and synthesis of Ti-containing mesoporous materials have been reviewed. Various strategies for the preparation of Ti-containing rnesoporous materials, such as direct synthesis and post-synthesis, are described. Modifications of Ti-containing mesoporous materials by surface-grafting and atom-planting are also discussed. All approaches aimed mainly at the improving of the stability, the hydrophobicity, and mostly the catalytic activity. Structural and mechanistic features of various synthetic systems are discussed. Ti-containing mesoporous materials in liquid phase catalytic oxidation of organic compounds with H2O2 as an oxidant is briefly summarized, showing their broad utilities for green synthesis of fine chemicals by catalytic oxidative reactions.  相似文献   

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Ionic liquids are credited with a number of unusual properties. These include a low vapor pressure, a wide liquid‐phase range, weakly coordinating properties, and a high thermal/chemical stability. These properties are certainly of great interest for inorganic synthesis and the creation of novel inorganic compounds. On the other hand, the synthesis repertoire for preparing inorganic compounds has always been broad, ranging from syntheses in solutions and melts to solid‐state reactions, and from crystal growth in the gas phase to high‐pressure syntheses. What new aspects can ionic liquids then add to the synthesis of inorganic compounds? This Minireview uses some early examples to show that the use of ionic liquids indeed provides access to unusual inorganic compounds.  相似文献   

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Multiwall carbon nanotube-supported Pt (Pt/MWNTs) catalysts with high dispersion and high loading of Pt were prepared by chemical reduction method and the loading of Pt got to 40 wt%. The average diameter of Pt nanoparticles on MWNTs was about 3.5 nm. When the hydrogen and air were used as reactant gases for PEMFC, Pt/MWNTs catalysts showed significantly higher performance than the Pt/XC-72 (carbon black) catalysts.  相似文献   

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Circular polarized light in space might be responsible for the fact that amino acids isolated from meteorites are not racemic. For example, 1 has been found with an enantiomeric excess of up to 10.4%. Such radiation has now been observed for the first time.  相似文献   

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