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Two-dimensional fused aromatic networks (2D FANs) have emerged as a highly versatile alternative to holey graphene. The synthesis of 2D FANs with increasingly larger lattice dimensions will enable new application perspectives. However, the synthesis of larger analogues is mostly limited by lack of appropriate monomers and methods. Herein, we describe the synthesis, characterisation and properties of an expanded 2D FAN with 90-ring hexagons, which exceed the largest 2D FAN lattices reported to date.

In the present study we have applied Quantum Mechanical (QM) and Molecular Mechanics (MM) computational methods to solid state materials of interest, specifically: metal hydrides, olivines, ceria and tin oxide crystals.\ud \ud A new empirical potential set has been derived for the following metal hydrides; NaH, LiH, MgH2, CaH2 and BaH2. Studies of atomic diffusion have been performed in LiH and CaH2 and agree well with the available experimental data. MM simulations of cation diffusion in olivines have been performed. Diffusion has been found to come mainly from Mi-Mi nearest neighbour jumps with a smaller contribution by site exchange, MrM2 and M2-M1; jumps. The spatial exploration of non-linear diffusion paths has been shown crucial in order to yield correct estimations of the activation energy of diffusion. MM calculations of solution and clustering of Cu2+ in ceria show that, on the contrary to previous work, it is quite likely that the dopant enters in interstitials sites and, consequently all clusters observed experimentally may be formed by Cu2+ interstitials.\ud \ud QM cluster and periodic slab simulations have been performed on the CO and C02 adsorption on the (110) perfect surface of Sn02 with HF and DFT methods. These calculations show that, for CO, the molecule adsorbs on pentacoordinated cations on, ideal, truncated bulk, and relaxed surfaces. The interaction with the surface is mostly electrostatic and well described by uncorrelated methods. In the C02 case, the molecule adsorbs perpendicularly to the surface on the same site, but the main bonding contribution is the polarization of the C02 and DFT methods are necessary to properly describe the binding. Carbonates have been shown to be formed only as metastable species on the perfect (100) Sn02 surface.

We report the first Ru(ii) coordination compounds that interact with DNA through a canonical minor groove insertion mode and with selectivity for A/T rich sites., We report the first Ru(ii) coordination compounds that interact with DNA through a canonical minor groove insertion mode and with selectivity for A/T rich sites. This was made possible by integrating a bis-benzamidine minor groove DNA-binding agent with a ruthenium(ii) complex. Importantly, one of the enantiomers (Δ-[Ru(bpy)2b4bpy]2+, Δ-4Ru) shows a considerably higher DNA affinity than the parent organic ligand and the other enantiomer, particularly for the AATT sequence, while the other enantiomer preferentially targets long AAATTT sites with overall lower affinity. Finally, we demonstrate that the photophysical properties of these new binders can be exploited for DNA cleavage using visible light.

Three-dimensional covalent organic frameworks (3D COFs) with a pcu topology have been obtained from distorted polycyclic aromatic hydrocarbons acting as triangular antiprismatic (D3d) nodes. Such 3D COFs are six-fold interpenetrated as the result of interframework ?-stacking, which enable charge transport properties that are not expected for 3D COFs.

Understanding charge transport in 2D covalent organic frameworks is crucial to increase their performance. Herein a new wavy 2D covalent organic framework has been designed, synthesized and studied to shine light on the structural factors that dominate charge transport.

Three-dimensional covalent organic frameworks (3D COFs) with a pcu topology have been obtained from distorted polycyclic aromatic hydrocarbons acting as triangular antiprismatic (D3d) nodes. Such 3D COFs are six-fold interpenetrated as the result of interframework π-stacking, which enable charge transport properties that are not expected for 3D COFs.

Herein we report the synthesis of covalently functionalized carbon nano-onions (CNOs) via a reductive approach using unprecedented alkali-metal CNO intercalation compounds. For the first time, an in situ Raman study of the controlled intercalation process with potassium has been carried out revealing a Fano resonance in highly doped CNOs. The intercalation was further confirmed by electron energy loss spectroscopy and X-ray diffraction. Moreover, the experimental results have been rationalized with DFT calculations. Covalently functionalized CNO derivatives were synthesized by using phenyl iodide and n-hexyl iodide as electrophiles in model nucleophilic substitution reactions. The functionalized CNOs were exhaustively characterized by statistical Raman spectroscopy, thermogravimetric analysis coupled with gas chromatography and mass spectrometry, dynamic light scattering, UV−vis, and ATR-FTIR spectroscopies. This work provides important insights into the understanding of the basic principles of reductive CNOs functionalization and will pave the way for the use of CNOs in a wide range of potential applications, such as energy storage, photovoltaics, or molecular electronics.

The effect of polypropylene (PP) on the Seebeck coefficient (S) of carbon nanofibers (CNFs) in melt-extruded PP composites filled with up to 5 wt. % of CNFs was analyzed in this study. The as-received CNFs present an electrical conductivity of ~320 S m−1 and an interesting phenomenon of showing negative S-values of −5.5 μVK−1, with 10−2 µW/mK2 as the power factor (PF). In contrast, the PP/CNF composites with 5 wt. % of CNFs showed lower conductivities of ~50 S m−1, less negative S-values of −3.8 μVK−1, and a PF of 7 × 10−4 µW/mK2. In particular, the change in the Seebeck coefficient of the PP/CNF composites is explained by a slight electron donation from the outer layers of the CNFs to the PP molecules, which could reduce the S-values of the as-received CNFs. Our study indicates that even insulating polymers such as PP may have a quantifiable effect on the intrinsic Seebeck coefficient of carbon-based nanostructures, and this fact should also be taken into consideration to tailor conductive polymer composites with the desired thermoelectric (TE) properties., The authors affiliated with 2C2T acknowledge support from FCT-Foundation for Science and Technology within the scope of project UID/CTM/00264/2020. In addition, support through project IF/ A. J. Paleo et al. 00894/2015 and within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020 and access to the Navigator platform (LCA-UC) through the Advanced Computing Project CPCA/A2/2524/2020, financed by national funds through the Portuguese Foundation for Science and Technology I.P./ MCTES, is gratefully acknowledged.

Herein, we report the synthesis of mechanically-interlocked nitrogenated nanographenes. These systems have been obtained by clipping different tetralactam macrocycles around a 1.9 nm dumbbell-shaped nitrogenated nanographene. Thermal, optoelectronicand electrochemicalcharacterization of the different mechanically-interlocked nanographenes evidence enhanced thermal and photochemical stability, and also,absorption and emission properties that vary with the structure of the macrocycle.