In this paper it is demonstrated that the stabilizing effect of linear alkanes can be utilized to achieve very high stability in the adsorption and assembly of planar organic molecules on inert surfaces under ambient conditions, by direct deposition from solutions. Using peripherally alkylated phthalocyanines and porphyrins as the examples, optimal resolutions can be achieved with complex molecular systems. Submolecular features of the molecular cores and the interdigitated alkyl parts are clearly visible. Distinctly different packing symmetries were also observed and could be attributed to the intermolecular and adsorbate−substrate interactions. Appreciable contrast variations were also recorded with changing bias voltages. This approach could be adapted to the studies of other molecules to observe submolecular features and could be helpful in obtaining two-dimensional assemblies of monodispersed molecules, especially planar molecules.

New insights into the formation chemistry of chalcogenate-protected metal nanoparticles (NPs) synthesized via the well-known Brust-Schiffrin two-phase method are presented here. On the basis of Raman, NMR, and surface plasmon resonance characterizations, it is concluded that, before the formation of any metal-chalcogen bonds, metal nucleation centers/NPs are first formed inside the inverse micelles of the tetrabutylammonium bromide in the organic solvent, where the metal ions are reduced by NaBH(4). The ensuing formation of the metal-chalcogen bonds between the naked metal NPs inside the micelles and the organo-chalcogen ligands in the organic solvent is the mechanism by which the further growth of the metal core can be controlled. This proposed mechanism is further examined in the formation of Ag and Cu NPs.

The fixation of CO2into cyclic carbonates using the emerging ionic liquid (IL) technology is reviewed from a multi-scale viewpoint.

Fischer−Tropsch synthesis (FTS) is a classical topic of great significance because of the approach of post-petroleum times. For decades, people have attempted to develop iron-based FTS catalysts with high selectivity for lower olefins. By means of the anchoring effect and the intrinsic basicity of nitrogen-doped carbon nanotubes (NCNTs), iron nanoparticles were conveniently immobilized on NCNTs without surface premodification. The so-constructed Fe/NCNTs catalyst presents superb catalytic performance in FTS with high selectivity for lower olefins of up to 46.7% as well as high activity and stability. The excellent performance is well-correlated with enhanced dissociative CO adsorption, inhibition of secondary hydrogenation of lower olefins, and promoted formation of the active phase of χ-Fe 5 C 2 . All of these merits result from participation of the nitrogen, as revealed by our experimental characterization. These results may lead to a new strategy for exploring advanced FTS catalysts with abundant N-doped carbon nanostructures.

The microstructure of ionic liquids (ILs) has attracted much attention due to their relevance in physiochemical properties and behavior of ILs. The existence of clusters (or microheterogeneous structure) is one of the main features for many ILs, which provides fundamental information for understanding the performance of ILs in their applications. This perspective concentrates on the recent progresses in IL clusters research. Firstly, we give a brief introduction on the structure of clusters in neat ILs and IL solutions. Secondly, the possible formation mechanism of the IL clusters is described. Then, the effects of the clusters on the physicochemical properties, interfacial properties, confined geometry and assembly processes of ILs are discussed. Finally, we address the associated challenges and prospects on the future study of IL clusters.

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Using carboxyl functionalized porphyrin and phthalocyanine as building blocks and alkane derivatives as coadsorbates, two-dimensional hydrogen-bonded networks were formed on graphite surface and observed by scanning tunneling microscopy. The configuration of the hydrogen bonding in the 2-D structure of 5,10,-15,20-tetrakis (4-carboxylphenyl)-21H,23H-porphyrin (TCPP) is found to be different from that in the 3-D structure in bulk crystal. The difference of these structures from that expected from the bulk crystal is attributed to the effect of minimization of surface free energy in the 2-D system, which leads to close packing symmetry of molecules on the substrate.

Two sets of experiments were performed to unravel the high-temperature pyrolysis of tricyclo[5.2.1.0 2,6 ] decane (JP-10) exploiting high-temperature reactors over a temperature range of 1100 K to 1600 K Advanced Light Source (ALS) and 927 K to 1083 K National Synchrotron Radiation Laboratory (NSRL)with residence times of a few tens of microseconds (ALS) to typically 144 ms (NSRL). The products were identified in situ in supersonic molecular beams via single photon vacuum ultraviolet (VUV) photoionization coupled with mass spectroscopic detection in a reflectron time-of-flight mass spectrometer (ReTOF). These studies were designed to probe the initial (ALS) and also higher order reaction products (NSRL) formed in the decomposition of JP-10 -including radicals and thermally labile closed-shell species. Altogether 43 products were detected and quantified including C1-C4 alkenes, dienes, C3-C4 cumulenes, alkynes, eneynes, diynes, cycloalkenes, cyclo-dienes, aromatic molecules, and most important, radicals such as ethyl, allyl, and methyl produced at lower residence times. At longer residence times, the predominant fragments are molecular hydrogen (H2), ethylene (C2H4), propene (C3H6), cyclopentadiene (C5H6), cyclopentene (C5H8), fulvene (C6H6), and benzene (C6H6).Accompanied by electronic structure calculations, the initial JP-10 decomposition via C-H bond cleavages resulting in the formation of initially six C10H15 radicals were found to explain the formation of all products detected in both sets of experiments. These radicals are not stable under the experiment conditions and further decompose via C-C bond -scission processes. These pathways result in ring opening in the initial tricyclic carbon skeletons of JP-10. Intermediates accessed after the first -scission can further isomerize or dissociate. Complex PAH products in the NRLS experiment (naphthalene, acenaphthylene, biphenyl) are likely formed via molecular growth reactions at elevated residence times.3