One-dimensional nanostructures of SnO 2 with a ribbonlike morphology have been prepared in large scale via rapid oxidation of elemental tin at 1080 °C. The products were characterized with scanning electron microscopy, X-ray powder diffraction, transmission electron microscopy, Raman scattering, and photoluminescence spectroscopy. The as-synthesized SnO 2 nanoribbons appeared to be single crystals and had preferred [110] and [203] growth directions. The lengths of the nanoribbons were up to several hundreds of micrometers, and the typical width and thickness were in the range of 30-150 nm and 10-30 nm, respectively. The strong photoluminescence of the nanoribbons in the visible region suggested possible applications in nanoscaled optoelectronic devices. A possible growth mechanism for the SnO 2 nanoribbons was proposed.

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Strong metal–support interactions (SMSI) is an important concept in heterogeneous catalysis. Herein, we demonstrate that the Au‐TiO2 SMSI of Au/TiO2 catalysts sensitively depends on both Au nanoparticle (NP) sizes and TiO2 facets. Au NPs of ca. 5 nm are more facile undergo Au‐TiO2 SMSI than those of ca. 2 nm, while TiO2 {001} and {100} facets are more facile than TiO2{101} facets. The resulting capsulating TiO2−x overlayers on Au NPs exhibit an average oxidation state between +3 and +4 and a Au‐to‐TiO2−x charge transfer, which, combined with calculations, determines the Ti:O ratio as ca. 6:11. Both TiO2−x overlayers and TiO2−x‐Au interface exhibit easier lattice oxygen activation and higher intrinsic activity in catalyzing low‐temperature CO oxidation than the starting Au‐TiO2 interface. These results advance fundamental understanding of SMSI and demonstrate engineering of metal NP size and oxide facet as an effective strategy to tune the SMSI for efficient catalysis.

Graphene nanoribbons (GNRs) are of enormous research interest as a promising active component in electronic devices, for example, field-effect transistors (FET). The recently developed "bottomup" on-surface synthesis provides an unprecedented approach for the generation of GNRs on metal surfaces with atomic precision. In order to fabricate well-defined GNRs on surfaces, numerous previous works have been focused on the delicate engineering of building blocks. Lateral fusion of polyphenylene chains into GNRs, as a more flexible method, now has received an increasing attention. However, the lateral fusion into GNRs reported to date is merely limited to the straight GNRs. The GNRs with other topologies potentially displaying distinctive electronic properties are rarely reported. In this work, we report the synthesis of armchair-edged graphene nanoribbons (AGNRs) with zigzag topology for the first time via a stepwise polymerization reaction starting from 4,4″-dibromo-m-terphenyl (DMTP) precursor on Au(111). Self-assembled unreacted monomers, covalent dimers, and zigzag polyphenylene chains are observed at different temperatures. Various GNRs with zigzag topology, including 6-AGNRs, 9-AGNRs, and nanoporous AGNRs are eventually produced through lateral fusion of polyphenylene chains. This study further diversifies the GNR family. Confining the zigzag polyphenylene chains in an ideal arrangement for subsequent lateral fusion can be explored in the future.