A series of novel m-arene-bridged salicylaldimine-based binuclear neutral nickel(II) complexes (2,4,6-(R 2 ) 3 C 6 H-1,3-[NdCH-4-X-6-R 1 C 6 H 2 ONi(Ph)(PPh 3 )] 2 (3a-i: R 1 , R 2 , X ) Me, Me, H (3a), t Bu, Me, H (3b), Me, Et, H (3c), t Bu, Et, H (3d), H, i Pr, H (3e), Me, i Pr, H (3f), t Bu, i Pr, H (3g), Ph, i Pr, H (3h), NO 2 , i Pr, NO 2 (3i), H, i Pr, NO 2 (3j)) are synthesized. The structure of complex 3h is further confirmed by an X-ray diffraction study showing that the two Ni centers adopt an unsymmetrical, distorted square planar geometry. In the presence or absence of the phosphine scavenger Ni(COD) 2 , complexes 3a-j show high catalytic activities for ethylene polymerization. The effect of substituents on ethylene polymerization is significant. The introduction of an electron-withdrawing group to the ligand framework improves the catalytic activity significantly. The influence of polymerization temperature, polymerization time, and catalyst concentration on the activities of ethylene polymerization is also investigated. Highly branched polyethylenes (46-127 branches per 1000 carbon atoms) with moderate molecular weights (M η ) (1.0-169) × 10 4 ) and narrow molecular weight distributions (M w /M n ) 2.3-2.4) are obtained by using complexes 3a-j as catalysts with or without a phosphine scavenger. In the presence of a polar solvent such as THF or Et 2 O, complex 3h polymerizes ethylene as a single-component catalyst. In comparison to the corresponding mononuclear Ni catalysts, the binuclear Ni catalysts generally show higher thermal stability, and complexes 3a, 3c, 3e, and 3f, which feature small R 1 substituents, are capable of acting as single-component ethylene polymerization catalysts.

RuO2/SnO2 catalysts with 2, 5 and 10 % Ru loadings were prepared with calcined and uncalcined SnO2 supports by the impregnation method. The catalysts were evaluated for CO and CH4 oxidation and characterised by N2‐BET, XRD, hydrogen temperature programmed reduction (H2‐TPR), energy‐dispersive X‐ray spectroscopy scanning electron microscopy (EDS‐SEM) and thermogravimetric analysis differential scanning calorimetry (TGA‐DSC). Owing to the synergetic effect between RuO2 and SnO2, all RuO2/SnO2 catalysts are found to be much more active than pure SnO2 and RuO2/Al2O3 for both CO and CH4 oxidation. For RuO2 supported on uncalcined SnO2, H2‐TPR and TGA‐DSC analysis revealed the formation of a new, less active compound between Sn and Ru that consumed active SnO2 and RuO2, and could be detrimental to the synergism between RuO2 and SnO2, and thus the activity of RuO2/SnO2 catalytic system. As a consequence, it is much less active than RuO2 supported on calcined SnO2. RuO2/SnO2 catalysts are also very stable in the presence of water vapour, which gives them potential for application in after‐treatment processes.

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The organization of molecular motors in supra­molecular assemblies to allow the amplification and transmission of motion and collective action is an important step toward future responsive systems. Metal-coordination-driven directional self-assembly into supra­molecular metalla­cycles provides a powerful strategy to position several motor units in larger structures with well-defined geometries. Herein, we present a pyridyl-modified molecular motor ligand (MPY) which upon coordination with geometrically distinct di-Pt­(II) acceptors assembles into discrete metalla­cycles of different sizes and shapes. This coordination leads to a red-shift of the absorption bands of molecular motors, making these motorized metalla­cycles responsive to visible light. Photochemical and thermal isomerization experiments demonstrated that the light-driven rotation of the motors in the metalla­cycles is similar to that in free MPY in solution. CD studies show that the helicity inversions associated with each isomerization step in the rotary cycle are preserved. To explore collective motion, the trimeric motor-containing metalla­cycle was aggregated with heparin through multiple electrostatic interactions, to construct a multi-component hierarchical system. SEM, TEM, and DLS measurements revealed that the photo- and thermal-responsive molecular motor units enabled selective manipulation of the secondary supra­molecular aggregation process without dissociating the primary metalla­cycle structures. These visible-light-responsive metalla­cycles, with intrinsic multiple rotary motors, offer prospects for cooperative operations, dynamic hierarchical self-assembled systems, and adaptive materials.

As the technology development, the future advanced combustion engines must be designed to perform at a low temperature. Thus, it is a great challenge to synthesize high active and stable catalysts to resolve exhaust below 100 °C. Here, we report that bismuth as a dopant is added to form platinum-bismuth cluster on silica for CO oxidation. The highly reducible oxygen species provided by surface metal-oxide (M-O) interface could be activated by CO at low temperature (~50 °C) with a high CO2 production rate of 487 μmolCO2·gPt−1·s−1 at 110 °C. Experiment data combined with density functional calculation (DFT) results demonstrate that Pt cluster with surface Pt−O−Bi structure is the active site for CO oxidation via providing moderate CO adsorption and activating CO molecules with electron transformation between platinum atom and carbon monoxide. These findings provide a unique and general approach towards design of potential excellent performance catalysts for redox reaction.