Fabrication and Catalytic Properties of Films Based on Metal Ion-ligand Interaction between K_2PdCl_4 and 3-Amino-3-(4-pyridinyl)-propionitrile

This work presents a highly active and reusable heterogeneous film catalytic assembly for hydrogenation reduction of aromatic nitro compounds. The multilayer structures of PEI-(K2PdCl4-P1)n-film(PEI = polyethylenmine, P1 = 3-amino-3-(4-pyridinyl)-propionitrile) bound to quartz slides were fabricated by layer-by-layer(LbL) self-assembly method. Various characterization techniques including X-ray photoelectron spectroscopy(XPS), inductively coupled plasma OES spectrometer(ICP), UV-vis spectroscopy and atomic force microscopy(AFM) were employed to reveal the growth process of the resulting LbL multilayers in detail. Subsequent in situ reduction by H2 produced Pd nanoparticles embedded in such films were used as catalyst for the hydrogenation of nitroarenes. The catalytic performance test shows that the thin film catalyst can be applied to the hydrogenation reaction of various substituted nitroaromatics, and exhibits good catalytic activity and good catalyst stability. It is worth mentioning that our catalytic films can be easily removed from the reaction system in any time during the reaction, and the catalytic activity could be fully recovered when reused directly in another catalytic cycle for five times.     

Nitrogen Doped Carbon as Efficient Catalyst toward Oxygen Reduction Reaction

A kind of nitrogen-doped carbon(NC) nanomaterials was prepared via calcining the nitrogen-rich organic molecular glycoluril under nitrogen atmosphere. Elemental analysis result indicates the N content of the obtained NC is 13.9 wt.%. Electrochemical measurement demonstrated that the obtained NC catalyst is an efficient ORR electrocatalyst in alkaline electrolyte. The process of ORR is dominated by a four-electron transfer pathway with the most efficient catalytic activity. In addition, the NC catalyst exhibits excellent stability and good resistance to methanol poisoning. After 10000 s of chronoamperometric durability test, the relative current of NC catalyst retained as high as 95%. This work provides a new strategy for the preparation of cost-effective ORR catalysts with high catalytic performance.     

Synthesis and Crystal Structure of a New Noble Metalcontaining Supramolecular Self-assembly with Decamethylcucurbit[5]uril

A new supramolecular self-assembly [Li(H2 O)2]2[(H2 O@Me10 CB[5])][PtC l6]·7 H2 O(1, Me10 CB[5] = decamethylcucurbit[5]uril), has been successfully constructed with Me10 CB[5] and [PtCl6]^2- anion in the presence of lithium cation(Li+). Single-crystal X-ray diffraction study reveals that compound 1 crystallizes in monoclinic space group P21/n with a = 11.1681(18), b = 28.5425(4), c = 18.9342(3) ?, β = 99.0143(15)°, V = 5961.02(16) ?~3, Z = 4, F(000) = 3224, μ = 2.714 mm^-1, R = 0.0470 and wR = 0.1076(I > 2σ(I)). In the supramolecular self-assembly, two of the portal carbonyl oxygen atoms of Me10 CB[5] are coordinated to Li+ cation, yielding a "half-open" molecular capsule. Then adjacent molecular capsules are connected with each other through hydrogen-bonding to form a one-dimensional(1 D) supramolecular chain structure. The [PtCl6]^2- anions are fixed on one side of the 1 D supramolecular chain through supramolecular interactions. The thermal stability, electronic valence and morphology of compound 1 are also investigated.