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Nanografting is used to create spatial confinement, which enables regulation of self-assembly reaction pathways and outcome. The degree and outcome of this regulation is revealed using binary self-assembled monolayers (SAMs) of organothiols and disulfides. In naturally grown systems, these SAMs have more complex morphology when compared with corresponding binary alkanethiol SAMs. Taller molecules form nanodomains of ellipsoidal cap in shape. These domains arrange in various irregular geometries, including 1D worm-like and 2D branches. This observation differs from binary alkanethiol SAMs, where nanodomains are separated and randomly dispersed. During nanografting, more homogeneous morphology was observed compared with naturally grown layers. By varying nanoshaving speed, the nanodomain structure can be regulated from randomly dispersed to more heterogeneous and, finally, to near natural growth. This trend is very similar to mixed alkanethiol systems, where the domain size and separation increase with increasing speed. Different from the alkanethiol systems, the observed structural variations are due to the changes in surface composition, in addition to domain size, shape, and arrangement.

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Construction of 2D graphic carbon nitrides (g‐CNx) with wide visible light adsorption range and high charge separation efficiency concurrently is of great urgent demand and still very challenging for developing highly efficient photocatalysts for hydrogen evolution. To achieve this goal, a two‐step pyrolytic strategy has been applied here to create ultrathin 2D g‐CNx with extended the π‐conjugation. It is experimentally proven that the extension of π‐conjugation in g‐CNx is not only beneficial to narrowing the bandgap, but also improving the charge separation efficiency of the g‐CNx. As an integral result, extraordinary apparent quantum efficiencies (AQEs) of 57.3% and 7.0% at short (380 nm) and long (520 nm) wavelength, respectively, are achieved. The formation process of the extended π‐conjugated structures in the ultrathin 2D g‐CNx has been investigated using XRD, FT‐IR, Raman, XPS, and EPR. Additionally, it has been illustrated that the two‐step pyrolytic strategy is critical for creating ultrathin g‐CNx nanosheets with extended π‐conjugation by control experiments. This work shows a feasible and effective strategy to simultaneously expand the light adsorption range, enhance charge carrier mobility and depress electron‐hole recombination of g‐CNx for high‐efficient photocatalytic hydrogen evolution.

For Rh2-organic molecular wires, we found that weaker coupling systems built using longer bridging ligands exhibit better electrical conductance.