As an organic nanostructure, self-assembled monolayers (SAMs) play a central role in many aspects of nanotechnology, including molecular electronics. In this work, we show that SAMs based on N-heterocyclic carbenes on a Au(111) substrate offer a high level of crystallinity and also exhibit the highest possible packing density. As a result of this structural optimization, defect concentrations were reduced by 2–3 orders of magnitude and thermal stability was ∼100 K higher than those of any other SAMs on Au. The conductivity of these SAMs is ∼4 orders of magnitude lower than that of standard alkanethiols of comparable length, which together with very low defect concentration and high thermal stability makes them a highly interesting material for potential application in organic thin film transistors. The self-assembly of such dense, highly crystalline, and notably stable structures is associated with strong C–Au bonding and the rational design of assembled molecules, resulting in the high mobility of both adsorbate and substrate atoms, as confirmed by the size of the molecular domains and the adsorbate-driven modification of the Au(111) substrate, respectively.

The electron-irradiation-induced synthesis of carbon nanomembranes (CNMs) from aromatic thiol-based self-assembled monolayers (SAMs) on gold substrate is a well-established method to form molecular thin nanosheets. These molecular two-dimensional materials can be prepared with tunable properties; therefore, they find a variety of applications in nanotechnology ranging from ultrafiltration to nanobiosensors. However, no chemically inert CNM was fabricated up to now, as the reactive thiol group is present on the membrane surface even after transferring it to other substrates. Here, we study the electron irradiation of carboxylic acid-based SAMs on a silver substrate as an alternative route for CNM formation. Our analysis, based on a combination of X-ray photoelectron spectroscopy and scanning electron microscopy demonstrates that for this type of SAMs, purely carbonaceous CNMs with tunable porosity can be obtained.

The activity of ceria-zirconia-supported nickel catalysts (Ni/CZ) with various loadings of nickel (2, 4 and 10 wt. %) was studied in the case of low-temperature dry reforming of methane (DRM). XRD, S BET , SEM, TPD-CO 2 and thermogravimetry were used to determine the physicochemical properties of the catalysts and of the carbon deposits formed on the surface. It was found that the agglomerates of the Ni-active phase are formed on the surface of the support for high loadings of nickel. The best conversions of CO 2 and CH 4 and an optimum ratio H 2 /CO = 1 were obtained for the catalysts with the highest Ni content. It was also found that loading has an influence on the amount of carbon deposits formed in the DRM process.

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