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1.
Proton storage in rechargeable aqueous zinc-ion batteries (ZIBs) is attracting extensive attention owing to the fast kinetics of H+ insertion/extraction. However, it has not been achieved in organic materials-based ZIBs with a mild electrolyte. Now, aqueous ZIBs based on diquinoxalino [2,3-a:2′,3′-c] phenazine (HATN) in a mild electrolyte are developed. Electrochemical and structural analysis confirm for the first time that such Zn–HATN batteries experience a H+ uptake/removal behavior with highly reversible structural evolution of HATN. The H+ uptake/removal endows the Zn–HATN batteries with enhanced electrochemical performance. Proton insertion chemistry will broaden the horizons of aqueous Zn–organic batteries and open up new opportunities to construct high-performance ZIBs.  相似文献   

2.
Radio-photoluminescence (RPL) materials display a distinct radiation-induced permanent luminescence center, and therefore find application in the detection of ionizing radiation. The current inventory of RPL materials, which were discovered by serendipity, has been limited to a small number of metal-ion-doped inorganic materials. Here we document the RPL of a metal–organic framework (MOF) for the first time: X-ray induced free radicals are accumulated on the organic linker and are subsequently stabilized in the conjugated fragment in the structure, while the metal center acts as the X-ray attenuator. These radicals afford new emission features in both UV-excited and X-ray excited luminescence spectra, making it possible to establish linear relationships between the radiation dose and the normalized intensity of the new emission feature. The MOF-based RPL materials exhibit advantages in terms of the dose detection range, reusability, emission stability, and energy threshold. Based on a comprehensive electronic structure and energy diagram study, the rational design and a substantial expansion of candidate RPL materials can be anticipated.  相似文献   

3.
1 INTRODUCTION Metal-organic compounds with open-frameworks are of intense interest due to their potential appli- ciations in the fields of molecular sieving, optical materials, zeolitic catalyses and so forth[1~9]. Addi- tionally, their functionality can be modified by chan- ging either the inorganic species or the organic li- gands in the structures. In the past decade, one di- mensional (1-D) infinite sructure with specific topo- logies has been obtained by assembly of suitable metal …  相似文献   

4.
A novel organic soluble and thermal-stable fullerene-perylene dyad, in which a perylenemoietyis attached to C60, has been prepared by 1, 3-dipolar cycloaddition of the azomethine ylidesgenerated in situ from the aldehyde and N-methylglycine and characterized by NMR, FT-IR, TGA,absorption and fluorescent spectra etc.  相似文献   

5.
A novel organic chromophore 4, 4'-bis(9-carbazyl-trans-styryl)-biphenyl (BCSBP) has been synthesized and characterized by IHNMR and elemental analysis. Three-photon absorption(3PA) induced upconvention fluorescence was observed and large 3PA cross section as high as 10^-74 cm^6 s^2 was obtained for nanosecond laser pulses at 1064 nm from optical limiting measurements.  相似文献   

6.
Metal–organic cages (MOCs), which are formed via coordination-driven assembly, are being extensively developed for various applications owing to the utility of their accessible molecular-sized cavity. While MOC structures are uniquely and precisely predetermined by the metal coordination number and ligand configuration, tailoring MOCs to further modulate the size, shape, and chemical environment of the cavities has become intensively studied for a more efficient and adaptive molecular binding. Herein, we report self-expanding MOCs that exhibit remarkable structural variations in cage size and flexibility while maintaining their topology. A cyclic ligand with an oligomeric chain tethering the two benzene rings of stilbene was designed and mixed with RhII ions to obtain the parent MOCs. These MOCs were successfully transformed into expanded MOCs via the selective cleavage of the double bond in stilbene. The expanded MOCs could effectively trap multidentate N-donor molecules in their enlarged cavity, in contrast to the original MOCs with a narrow cavity. As the direct synthesis of expanded MOCs is impractical because of the entropically disfavored structures, self-expansion using ring-openable ligands is a promising approach that allows precision engineering and the production of functional MOCs that would otherwise be inaccessible.  相似文献   

7.
A triphosphaazatriangulene (H3L) was synthesized through an intramolecular triple phospha-Friedel–Crafts reaction. The H3L triangulene contains three phosphinate groups and an extended π-conjugated framework, which enables the stimuli-responsive reversible transformation of [Cu(HL)(DMSO)⋅(MeOH)]n, a 3D-MOF that exhibits reversible sorption characteristics, into (H3L⋅0.5 [Cu2(OH)4⋅6 H2O] ⋅4 H2O), a 1D-columnar assembled proton-conducting material. The hydrophilic nature of the latter resulted in a proton conductivity of 5.5×10−3 S cm−1 at 95 % relative humidity and 60 °C.  相似文献   

8.
Methanol is used as a common solvent, cost-effective reagent, and sustainable feedstock for value-added chemicals, pharmaceuticals, and materials. Among the various applications, the utilization of methanol as a C1 source for the formation of carbon–carbon, carbon–nitrogen, and carbon–oxygen bonds continues to be important in organic synthesis and drug discovery. In particular, the synthesis of C-, N-, and O-methylated products is of central interest because these motifs are found in a large number of natural products as well as fine and bulk chemicals. In this Minireview, we summarize the utilization of methanol as a C1 source in methylation, methoxylation, formylation, methoxycarbonylation, and oxidative methyl ester formation reactions.  相似文献   

9.
Engineering coordinated rotational motion in porous architectures enables the fabrication of molecular machines in solids. A flexible two-fold interpenetrated pillared Metal-Organic Framework precisely organizes fast mobile elements such as bicyclopentane (BCP) (107 Hz regime at 85 K), two distinct pyridyl rotors and E-azo group involved in pedal-like motion. Reciprocal sliding of the two sub-networks, switched by chemical stimuli, modulated the sizes of the channels and finally the overall dynamical machinery. Actually, iodine-vapor adsorption drives a dramatic structural rearrangement, displacing the two distinct subnets in a concerted piston-like motion. Unconventionally, BCP mobility increases, exploring ultra-fast dynamics (107 Hz) at temperatures as low as 44 K, while the pyridyl rotors diverge into a faster and slower dynamical regime by symmetry lowering. Indeed, one pillar ring gained greater rotary freedom as carried by the azo-group in a crank-like motion. A peculiar behavior was stimulated by pressurized CO2, which regulates BCP dynamics upon incremental site occupation. The rotary dynamics is intrinsically coupled to the framework flexibility as demonstrated by complementary experimental evidence (multinuclear solid-state NMR down to very low temperatures, synchrotron radiation XRD, gas sorption) and computational modelling, which helps elucidate the highly sophisticated rotor-structure interplay.  相似文献   

10.

Single-drop microextraction (SDME) and hollow-fiber membrane microextraction (HFME) belong to methods of the liquid-phase microextraction preconcentration of organic compounds. These methods are characterized by the low consumption of organic solvents, high preconcentration factors, simplicity, low cost, ease of combination with various chromatographic methods; processes of preconcentration and sample injection are combined in a single device. Since the emergence of SDME (1996) and HFME (1999), a large number of versions have been developed that differ in the preconcentration technique, nature of the extractants used, and combinations with methods for the subsequent determination of the preconcentrated substances. The popularity of these methods among the analysts is evidenced by many reviews that we have summarized in this publication.

  相似文献   

11.
The use of microwave technology in accelerating organic reactions has received intense attention leading to immense growth recently. Accordingly, we have been interested in improving the efficacy of organic processes by microwave irradiation. Here we report our results on the microwave assisted direct amide formation from carboxylic acid and amine, the hydrolysis of biopolymers, and nucleophilic aromatic substitution reaction. The reactions carried out under microwave irradiation, in general, …  相似文献   

12.
陈竹雯 《大学化学》1988,3(6):37-37
本书由Dean,J.A.编著,由McGraw—Hill在1987年出版。它以表格形式按英文字母顺序给出了4000种有机化合物及与有机化学相关的无机化合物的名称、结构式、分子量、Beilstein文献、密度、折光指数、熔点、沸点、闪点和溶解度。其中一部分还给出了物理性质(包括粘度、介电常数、偶极矩和表面张力)、  相似文献   

13.
The research on up-conversion photoluminescence of organic materials is a hot topic1, most recently, the up-conversion laser properties of organic materials with big two- photon absorption cross section have been noticed especially2. According to the prev…  相似文献   

14.
Preparation of Pt/C Catalyst with a New and Simple Organic Sol Method   总被引:3,自引:0,他引:3  
It is reported for the first time that the Pt/C catalyst can be prepared with a new and simple organic sol method using SnCl2 as the reductant. It was found that the average size of the Pt particles in the Pt/C catalysts could be controlled with controlling the preparation conditions. The effect of the average sizes of the Pt particles in the Pt/C catalysts obtained with this method on the electrocatalytical activity of the oxidation of methanol was investigated.  相似文献   

15.
Two-photon absorption (TPA) is a process in which two photons are simultaneously absorbed to an excited state via a virtual state. The synthesis of organic optical materials with large TPA cross section has become a subject of great interest in recent years due to various application such as three-dimensional fluorescence imaging1, optical data storage2,3 and lithographic microfabrication4-6. Recently we have synthesized a new organic dye DEAHAS that is a symmetrically substituted stilbe…  相似文献   

16.
In comparison with the fast development of binary mixture separations, ternary mixture separations are significantly more difficult and have rarely been realized by a single material. Herein, a new strategy of tuning the gate-opening pressure of flexible MOFs is developed to tackle such a challenge. As demonstrated by a flexible framework NTU-65, the gate-opening pressure of ethylene (C2H4), acetylene (C2H2), and carbon dioxide (CO2) can be regulated by temperature. Therefore, efficient sieving separation of this ternary mixture was realized. Under optimized temperature, NTU-65 adsorbed a large amount of C2H2 and CO2 through gate-opening and only negligible amount of C2H4. Breakthrough experiments demonstrated that this material can simultaneously capture C2H2 and CO2, yielding polymer-grade (>99.99 %) C2H4 from single breakthrough separation.  相似文献   

17.
IntroductionThepotentialforuseoftwo photonabsorbingmoleculesinapplicationsrangingfromopticallimiting1 3tothreedimensional (3D)fluorescencemicroscopy4 and 3Dmicrofabricationandopticaldatastorage5,6 hasstimulatedresearchonthedesign ,synthesis ,andcharacterizationofnewmoleculeswithlargetwo photonabsorptivities .7,8Thetwo photonabsorption (2PA)processconsideredherein volvesthesimultaneousabsorptionoftwophotons ,eitherdegeneratingornondegenerating ,atwavelengthswellbe yondthelinearabsorptionspectr…  相似文献   

18.
A new organic hybrid holmium–germanate oxo-cluster [Ho8(phen)2Ge12(μ 3-O)24(CH2CH2COO)12(H2O)16]·2H2O (1, phen = 1,10-phenanthroline) was prepared under mild hydrothermal conditions and structurally characterized by elemental analysis, UV/Vis, IR spectroscopy, thermogravimetric analysis, and powder X-ray diffraction. Compounds 1 contains cage clusters [Ho8(phen)2Ge12(μ 3-O)24(CH2CH2COO)12(H2O)16] and free H2O molecules. The cage cluster is constructed by the combination of two [Ho(phen)(H2O)2] units, two [Ge6O12(CH2CH2COO)6] rings and one circular [Ho6O36] fragment via sharing O atoms. 1 is the rare example of organic hybrid holmium–germanate oxo-cluster decorated by phen ligands.  相似文献   

19.
A study was conducted to evaluate the inclusion properties of various nonionic hydrophobic organic compounds by a novel intercalate derived from magnesium-aluminum layered double hydroxide (Mg/Al LDH) and carboxymethyl--cyclodextrin with a degree of substitution of 3 [CMCD(3)]. The isotherm sorption results at 25 °C showed that the CMCD(3)-Mg/Al LDH intercalate could retain all the organic compounds (trichloroethylene, tetrachloroethylene, benzene, toluene, p-, o-, m-xylene, ethylbenzene, 1,2,3-trichlorobenzene, naphthalene) studied and its sorption affinity for organic compounds was positively related to their hydrophobicities. The host-guest interaction was attributed to a partition process of the organic compounds into cyclodextrin cavities as well as intermolecular pores. A stereoselective interaction might also be involved due to the intercalation of CMCD(3) within Mg/Al LDH interlayers.  相似文献   

20.
Electrodeposition is an old and effective method for the fabrication of organic films. Though electrodeposited organic films have been widely used in various applications, highly luminescent films have been a great challenge because the electrochemically doped state may strongly quench the fluorescence. In the first part of this review, the organic electrodeposition techniques, along with general electropolymerization and other special electrodepositions are introduced. In the second part of the...  相似文献   

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