Design and synthesis of metal sulfide catalysts supported on zeolite nanofiber bundles with unprecedented hydrodesulfurization activities.

Developing highly active hydrodesulfurization (HDS) catalysts is of great importance for producing ultraclean fuel. Herein we report on crystalline mordenite nanofibers (NB-MOR) with a bundle structure containing parallel mesopore channels. After the introduction of cobalt and molybdenum (CoMo) species into the mesopores and micropores of NB-MOR, the NB-MOR-supported CoMo catalyst (CoMo/NB-MOR) exhibited an unprecedented high activity (99.1%) as well as very good catalyst life in the HDS of 4,6-dimethyldibenzothiophene compared with a conventional γ-alumina-supported CoMo catalyst (61.5%). The spillover hydrogen formed in the micropores migrates onto nearby active CoMo sites in the mesopores, which could be responsible for the great enhancement of the HDS activity.

Extraordinarily high activity in the hydrodesulfurization of 4,6-dimethyldibenzothiophene over Pd supported on mesoporous zeolite Y.

Design and preparation of highly active hydrodesulfurization (HDS) catalysts is very important for the removal of air pollution. Herein, we report an extraordinarily active HDS catalyst, which is synthesized by loading of Pd on mesoporous zeolite Y (Pd/HY-M). The mesoporous zeolite Y is successfully synthesized using a water glass containing N,N-dimethyl-N-octadecyl-N-(3-triethoxysilylpropyl) ammonium [(C(2)H(5)O)(3)SiC(3)H(6)N(CH(3))(2)C(18)H(37)](+) cation as a mesoscale template. Compared with mesoporous Beta and ZSM-5 supported Pd catalysts (80.0% and 73.4% for Pd/HBeta-M and Pd/HZSM-5-M, respectively) as well as commercial catalyst of γ-Al(2)O(3) supported Pd catalyst (31.4%), Pd/HY-M catalyst exhibited very high activity in HDS of 4,6-dimethyldibenzothiophene (4,6-DM-DBT, 97.3%). The higher activity of Pd/HY-M than that of Pd/HBeta-M and Pd/HZSM-5-M is assigned to the larger micropore size of zeolite Y compared to that of Beta and ZSM-5. Theoretical simulation and adsorption experimental data show that 4,6-DM-DBT has difficulty entering the micropores of ZSM-5 and Beta zeolites, but the micropores of Y zeolite are accessible.

Poly[[aqua(4,4'-diazenediyldibenzoato-kappa4O,O':O'',O''')cadmium(II)]: a twofold interpenetrated three-dimensional coordination polymer of PtS topology.

In the title coordination compound, [Cd(C14H8N2O4)(H2O)]n, the Cd(II) cation and the coordinated water molecule lie on a twofold axis, whereas the ligand lies on an inversion center. The Cd(II) center is five-coordinated in a distorted square-pyramidal geometry by four carboxylate O atoms from four different 4,4'-diazenediyldibenzoate (ddb) anions and one water O atom. The three-dimensional frameworks thus formed by the bridging ddb anions interpenetrate to generate a three-dimensional PtS-type network. Additionally, the coordination water molecule and the carboxylate O atom form a hydrogen-bonding interaction, stabilizing the three-dimensional framework structure.

Poly[(N,N-dimethylformamide-kappaO)(mu(3)-4,4'-ethylenedibenzoato-kappa(5)O,O':O':O'',O''')(pyrazino[2,3-f][1,10]phenanthroline-kappa(2)N(8),N(9))lead(II)].

In the title Pb(II) coordination polymer, [Pb(C(16)H(10)O(4))(C(14)H(8)N(4))(C(3)H(7)NO)](n), each Pb(II) atom is eight-coordinated by two chelating N atoms from one pyrazino[2,3-f][1,10]phenanthroline (L) ligand, one dimethylformamide (DMF) O atom and five carboxylate O atoms from three different 4,4'-ethylenedibenzoate (eedb) ligands. The eedb dianions bridge neighbouring Pb(II) centres through four typical Pb-O bonds and one longer Pb-O interaction to form a two-dimensional structure. The C atoms from the L and eedb ligands form C-H...O hydrogen bonds with the O atoms of eedb and DMF ligands, which further stabilize the structure. The title compound is the first Pb(II) coordination polymer incorporating the L ligand.

A six-connected alpha-polonium net based on tetranuclear Cd(II) nodes.

The cadmium(II) coordination polymer poly[[(pyrazino[2,3-f][1,10]phenanthroline-kappa(2)N(8),N(9))cadmium(II)]-mu(3)-naphthalene-1,4-dicarboxylato-kappa(5)O(1):O(1),O(1'):O(4),O(4')], [Cd(C(12)H(6)O(4))(C(14)H(8)N(4))](n), contains two Cd(II) cations, two pyrazino[2,3-f][1,10]phenanthroline (L) ligands and two naphthalene-1,4-dicarboxylate (1,4-ndc) anions in the asymmetric unit. Both Cd(II) ions are in a distorted CdO(5)N(2) monocapped octahedral coordination geometry. Both unique 1,4-ndc ligands are bonded to three Cd(II) ions. In these modes, tetranuclear clusters are formed in which four Cd(II) ions are bridged by the carboxylate groups of the 1,4-ndc ligands to form discrete rods. The tetranuclear cadmium carboxylate clusters act as rod-shaped secondary building units (SBUs) within the structure. The SBUs are connected together by the aromatic backbone of the dicarboxylate ligands, connecting the clusters into a three-dimensional alpha-polonium net. The title compound represents the first alpha-polonium net constructed from rod-like clusters in coordination polymers. The result indicates that an appropriate combination of dicarboxylate and aromatic chelating ligands is critical to the formation of high-dimensional structures based on metal clusters in these systems.

Heterogeneous Co-catalyzed direct 2-alkylation of azoles with ethers.

The direct 2-alkylation of oxazoles and thiazoles with ethers through cross-dehydrogenative coupling reaction using Co-containing mesoporous zeolite ETS-10 as the heterogeneous catalyst is described. The basic Co-containing mesoporous zeolite ETS-10 catalyst facilitates this cross-dehydrogenative coupling reaction through metal-base synergy catalytic principle.

Copper(i)-catalyzed radical decarboxylative imidation of carboxylic acids with N-fluoroarylsulfonimides.

An efficient copper-catalyzed radical decarboxylative imidation reaction is presented. This strategy is carried out through the copper(i)-catalyzed decarboxylative C(sp(3))-N and C(sp(2))-N coupling of carboxylic acids with N-fluoroarylsulfonimides. The reaction shows good functional group tolerance and it provides a new approach for decarboxylative imidation. Preliminary mechanistic studies of this transformation suggest an involvement of N-centered radical species.

Zeolite Y nanosheet assembled palladium catalysts with high catalytic activity and selectivity in the vinylation of thiophenes.

Zeolite Y nanosheets with a micro-meso-macroporous structure were synthesized, and applied in the assembly of a Pd catalyst (Pd/NS-Y) for direct vinylation of thiophenes with high activity and selectivity, as compared to Pd(OAc)2, Pd(NO3)2, and Pd(PPh3)4 catalysts. This feature should be assigned to the highly dispersed Pd(δ+) (δ < 2) species in Pd/NS-Y, which are more active than Pd(2+).

High activity and stability in the cross-coupling of aryl halides with disulfides over Cu-doped hierarchically porous zeolite ZSM-5.

A Cu-doped zeolite ZSM-5 (Cu-ZSM-5-M) with a micro-meso-macroporous structure was directly synthesized, and it exhibits excellent catalytic activity and good recyclability in the cross-coupling of aryl halides with diphenyl disulfides. This feature should be attributed to the structural characteristics of meso-macropores and homogeneous dispersion of active Cu(δ+) (δ < 2) species in Cu-ZSM-5-M.

Fabrication of microcavity-array superhydrophobic surfaces using an improved template method.

We fabricated the first superhydrophobic (SH) surface with microcavities, using a simple process. The process included an improved template method (ITM) for constructing the SH surface with cavities, using taro leaves as a pattern mask, and a dip-coating method for modifying the SH surface. The results obtained using the ITM are significantly better than those achieved using traditional template methods. In addition, the water-repellence of the microcavities surface was significantly enhanced by decorating with a layer of polymerized n-octadecylsiloxane nanosheets.

Fabrication of noble-metal catalysts with a desired surface wettability and their applications in deciphering multiphase reactions.

Noble-metal Pd and Pt catalysts with a wide range of surface wettability were fabricated through an electrochemical approach and were characterized with scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and atomic force microscopy. The importance of surface wettability of solid catalysts in multiphase reactions-especially their correlation to the nature of the studied chemical system-was investigated by reducing oxygen in an alkaline solution and oxidizing hydrogen peroxide and sodium formate in alkaline or buffered solutions at the as-prepared catalysts. These experiments illustrate that the nature of a multiphase reaction plays a critical role in determining the influence of surface wettability on the catalyst performance, providing a unique approach to decipher the reaction process. The investigation allows us to gain new insights into the electrochemical oxidation of sodium formate.

Single-crystal NaY(MoO4)2 thin plates with dominant {001} facets for efficient photocatalytic degradation of dyes under visible light irradiation.

Single-crystal NaY(MoO(4))(2) thin plates dominated by high-energy {001} facets were hydrothermally synthesized under relatively mild conditions, free of organic additives, seeds and templates. The as-obtained NaY(MoO(4))(2) thin plates showed an excellent visible-light-responding photocatalytic activity for degradation of dyes in water.

Facile preparation of superhydrophobic biomimetic surface based on octadecyltrichlorosilane and silica nanoparticles.

The present paper describes the simple and low-cost process for the production of a superhydrophobic surface with micronano hierarchical structure from the chemisorptions of SiO(2) nanoparticles onto polymerized n-octadecylsilane. The process was carried out under ambient conditions without the use of expensive equipment. The as-prepared micronano-binary films exhibited a very high contact angle of 179.9 degrees and a low contact hysteresis of 2.5 degrees . On the basis of the results of the characterization techniques, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and contact angle (CA) measurements, a formation mechnism of the superhydrophobic micronano structure was proposed. Drop impact experiments on the modified-glass substrate showed that the as-prepared films possess a high-impalement threshold.