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Magnesium doped ultra-fine RuO 2 nanoparticles are prepared by a one-step annealing of Ru-exchanged Mg-MOF-74. Mg-RuO 2 exhibits excellent oxygen evolution reaction performance with a low overpotential of 228 mV at 10 mA cm -2 . The excellent performance is attributed to the altered electronic structure and the optimized surface atomic arrangement.

We report on the two-dimensional self-assembly of C 2v -symmetric [1,1':3',1''-terphenyl]-3,3'',5,5''-tetracarboxylic acid (TPTA) at the solid/liquid interface by using scanning tunneling microscopy (STM). Two kinds of different self-assembly structure, i.e. a close-packed and porous rosette structure, are formed by TPTA molecules through intermolecular hydrogen bonds. When adding coronene (COR) as a guest into the TPTA assembly, structural transformation from a densely packed row structure to a rosette network structure is observed. It was found that two kinds of cavities with different sizes in the rosette network structure can be used to realize the selective co-adsorption of guest molecules with appropriate shape and size. Three-component 2D host-guest structures were successfully constructed by using 1,2,3,4,5,6-hexakis(4-bromophenyl)benzene (HBPBE) and copper phthalocyanine (CuPc) as guest molecules., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Three types of well-ordered covalent two-dimensional tilings including triangular, rhombille and semi-regular Archimedean tilings were successfully constructed via on-surface Schiff base reaction. Among them, the covalent organic framework (COF) constructed from a C6 symmetry monomer and C3 symmetry monomer is the first reported COF with kgd (rhombille tiling) topology.

Here we show a conceptual approach to realize the scanning tunneling microscopy based induced-assembly of fullerene (C60) molecules on top of a buffer organic adlayer at room temperature in a solution environment. The realization of spatially-defined C60 assembly is attributed to the modulation of substrate-molecular interactions with the assistance of a buffer layer.

Double-walled nanoporous networks based on the Schiff base reaction of nonplanar tripodic building blocks and subsequent dipole-directed self-assembly were fabricated on highly oriented pyrolytic graphite (HOPG) at the gas-solid interface. This is the first example of nonplanar molecules exploited as precursors for a surface reaction.

The introduction of intramolecular H-bonding by adding -OH functionalities adjacent to the Schiff base centers is considered to be a useful strategy to enhance the stability and crystallinity of bulk covalent organic frameworks (COFs). However, the influence of intramolecular H-bonding on the synthesis of surface COFs (SCOFs) have been barely explored. Herein, SCOFs based on the Schiff-base reaction between 1,3,5-tris(4-aminophenyl)benzene (TAPB) and terephthalaldehydes with symmetry or asymmetrically substituted hydroxyl functional groups are designed. In the absence of a solvent, hydroxyl substituents can be easily oxidized; thus argon protection is required to obtain high-quality SCOFs. Besides, an extended network with uniform pores can be achieved in spite of the symmetry of substituents. Both experimental results and theoretical calculations show that the influence of intramolecular hydrogen bonding on surface synthesis is not as important as that in bulk phase synthesis because the substrate itself can lead to the complanation of adsorbed molecules. The existence of intramolecular H-bonding can enhance the stability of the network in both acid and alkali environments.

We systematically studied the operation of coadsorber-induced surface chirality in a series of enantiomeric surface supramolecular assemblies. The correlation of chiral amplification degree with the proportion of enantiomeric interaction in the total intermolecular interaction is deduced.

A facile protocol is developed for the direct observation and characterization of a single particle electrode during the lithium ion battery operation by using in situ AFM. The SEI formation on the LiNi0.5Mn1.5O4 particle cathode surface is found to be highly related to the exposed planes.

A microscopic investigation of the molecular packing structures of a fused thiophene derivative reveals the important role of intermolecular S···S interaction in directing the 2D self-assembly. Thermal annealing of the assembly results in the irreversible phase transition to a new structure with different molecular trimeric packing motifs.

The self-assembly of truxenone on highly oriented pyrolytical graphite (HOPG) was investigated with scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. Truxenone assembled into a dense hexagonal adlayer with large and near-perfect domains on the graphite surface. Two types of topography image of truxenone were observed in experiments. DFT modeling indicates the center-hole image represents the contour of the lowest unoccupied molecular orbital (LUMO) of truxenone while the propeller-like image is more complicated and can't be assigned simply to an individual molecular orbital. Truxenone trimer was proposed as the basic unit of the adlayer through analysis of STM images and molecular structure. The optimized structure of the truxenone trimer by DFT calculation revealed that the hydrogen bonding network exists in the adlayer, which is responsible for the excellent stability and perfect domains of the whole assembly. In addition, the preferred adsorption site of truxenone on graphite was determined on the basis of DFT calculations and STM images. The results are of significance in supramolecular engineering by self-assembly and device fabrication based on truxenone and its derivatives.

The co-adsorption of trinitrotoluene (TNT), a typical π-electron acceptor, and triphenylene (TP), a typical π-electron donor, on a Au(111) surface was investigated by in situ Electrochemical Scanning Tunneling Microscopy (ECSTM). DFT calculations proved that parallelly stacked and well-overlapped TP and TNT molecules can form Donor-Acceptor dyads through intermolecular π-π charge transfer, which agree well with the experimental results in the present work., (This journal is © The Royal Society of Chemistry 2011)

Electrochemistry and adlayer structure of trinitrotoluene (TNT) on an Au(111) electrode were investigated using cyclic voltammetry and in situ electrochemical scanning tunneling microscopy (ECSTM).