Research

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    J. Am. Chem. Soc., 2017, 139 , 3669–3675

    Intermolecular C–C coupling after cleavage of C–X (mostly, X = Br or I) bonds has been extensively studied for facilitating the synthesis of polymeric nanostructures. However, the accidental appearance of C–H coupling at the terminal carbon atoms would limit the successive extension of covalent polymers. To our knowledge, the selective C–H coupling after dehalogenation has not so far been reported, which may illuminate another interesting field of chemical synthesis on surfaces besides in situ fabrication of polymers, i.e., synthesis of novel organic molecules. By combining STM imaging, XPS analysis, and DFT calculations, we have achieved predominant C–C coupling on Au(111) and more interestingly selective C–H coupling on Ag(111), which in turn leads to selective synthesis of polymeric chains or new organic molecules.

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    ACS Nano, DOI: 10.1021/acsnano.9b04835 Adv. Mater. 2019, 31, 1902606

    Since the mechanical exfoliation of graphene in 2004, two-dimensional (2D) materials have attracted considerable attention in the past decades for their superlative physical properties. Molecular beam epitaxy (MBE), one of the bottom-up approaches, has been used to fabricate numerous 2D materials for its accurate control of precursor and the growth condition. The group V 2D materials, such as phosphorene, antimonene, bismuthene, all have an intrinsic wide bandgap and high carrier mobility which are beneficial to the use in semiconductor devices. On the other hand, the 2D materials composed of heavy elements, Sb and Bi, exhibit quantum spin hall effect, specifically, the topological edge state, because of the strong spin orbit coupling. However, the fabrication of group V 2D materials and their properties need further research. We are devoted to fabricate large-scale, high-quality 2D materials via MBE and then observe in in-situ scanning tunneling microscopy (STM). We chose different substrates to observe the law of materials growth and the properties change, especially the electronic properties through interface design. At the same time, surveying the absorption and reaction of small molecular on the 2D materials surfaces can guide the applications in ambient atmosphere.


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    ChemistrySelect 2017, 2, 5793 – 5799

    A network of silica nanosheets composed of nanosheets of several nanometers in thickness and containing pores, whose dimensions are on the hundreds-of-nanometers scale, exhibits morphological self-adjustment upon binding of nanoparticles at its surface. The loading of nanoparticles in the nanosheets caused an obvious rearrangement of the silica nanosheet network probably due to the incomplete silica framework of the nanosheets. This self-adjustment of the structure leads to a fixing of the nanoparticles at the nanosheets’ interiors. In addition, the resulting gold nanoparticle-loaded silica nanosheets show high performance for the catalytic reduction of nitrophenols with high conversion. The networked nanosheets described here may be used as a new supporting substrate for other metal nanoparticles and could be used for various catalytic processes.


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    Phys. Chem. Chem. Phys. 2017, 19, 29099-29105

    Polycyclic aromatic compounds (naphthalene, anthracene and pyrene) have been intercalated into the superstructures of fullerene nanowhiskers, using a facile liquid–liquid interfacial precipitation (LLIP) method. Due to the interaction between polycyclic molecules and fullerene, the growth of fullerene crystals was interfered in comparison to the fullerene crystal growth without the polycyclic molecules, resulting in the formation of fullerene superstructures with various nanofeatures. Moreover, the fluorescence emissions of the fullerene superstructures were significantly changed due to the intercalation of the polycyclic molecules, implying the influence of molecular packing on the electron transfer within the nanostructures. These results may bring new insights on the control of fullerene nanostructures and to manipulate their optical properties in optoelectronic devices.

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    Langmuir, 2017, 33 (42), pp 11590–11602

    We have infused graphene/ionic liquid into block copolymer homoporous membranes (HOMEs), which have highly ordered uniform cylindrical nanopores, to form compact, dense, and continuous graphene/ionic liquid (Gr/IL) lubricating layers at interfaces, enabling a reduction in the friction coefficient. The loose graphene layers, which are caused by the coexistence of graphene and ILs, would make the sliding easier, and favor the lubrication. An increase in the friction coefficient was observed on ILs-infused block copolymer HOMEs, as compared to Gr/ILs-infused ones, due to the absence of Gr and the unstably formed ILs film. Gr/ILs-infused block copolymer HOMEs also exhibit much smaller residual indentation depth and peak indentation depth in comparison with ILs-infused ones. This indicates that the existence of stably supported Gr/ILs hybrid liquid films aids the reduction of the friction coefficient by preventing the thinning of the lubricant layer and exposure of the underlying block copolymer HOMEs.