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[EN]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. This work was carried out with support from the Basque Science Foundation for Science (Ikerbasque),POLYMAT, the University of the Basque Country,Gobierno Vasco (BERC programme) and Gobierno de España (Ministerio de Economía y Competitividad CTQ2016-77970-R).This work was performed under the Maria de Maeztu Units of Excellence Programme–Grant No.CEX-2019-000919-M Ministry of Science, nnovation and Universities.Technica land human support provided by SGIker of UPV/EHU and European funding (ERDFand ESF) is acknowledged.This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (GrantAgreementsNo.722951andNo.714122).This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreements No.664878 and No.899895. In addition,support through the project IF/00894/2015,the advanced computing project CPCA/A2/2524/2020 granting access to the Navigator cluster at LCA-UC and within the scope of the project CICECO-Aveiro Institute of Materials,UIDB/50011/2020&UIDP/50011/2020 funded by national fund sthrough thePortuguese Foundation for Science andTechnologyI. P./MCTES is gratefully acknowl-edged.The Nanoscale & Microscale Research Centre (nmRC), University of Nottingham,is acknowledged fore nabling access to electron microscopy facilities.

Controlled nitrogen-doping is a powerful methodology to modify the properties of carbon nanostructures and produce functional materials for electrocatalysis, energy conversion and storage, and sensing, among others. Herein, we report a wall- and hybridisation-selective synthetic methodology to produce double-walled carbon nanotubes with an inner tube doped exclusively with graphitic sp2-nitrogen atoms. Our measurements shed light on the fundamental properties of nitrogen-doped nanocarbons opening the door for developing their potential applications.

A range of mono- and bis-functionalised fullerenes have been synthesised and inserted into single-walled carbon nanotubes. The effect of the size and shape of the functional groups of the fullerenes on the resultant 1D arrays formed within the nanotubes was investigated by high resolution transmission electron microscopy and X-ray diffraction. The addition of non-planar, sterically bulky chains to the fullerene cage results in highly ordered 1D structures in which the fullerenes are evenly spaced along the internal nanotube cavity. Theoretical calculations reveal that the functional groups interact with neighbouring fullerene cages to space the fullerenes evenly within the confines of the nanotube. The addition of two functional groups to opposite sides of the fullerene cages results in a further increase in the separation of the fullerene cages within the nanotubes at the cost of lower nanotube filling rates., This work was financially supported by FWF project I83-N20 (ESF IMPrESS), the Royal Society, the European Research Council (ERC), "Fundacao para a Ciencia ea Tecnologia" through the program Ciencia 2008, the project SeARCH (Services and Advanced Research Computing with HTC/HPC clusters) and Nottingham Nanoscience and Nanotechnology Centre (NNNC).

Mechanisms for controlling the assembly of molecular arrays in carbon nanotubes via alteration of the size and geometry of the functional groups attached to the molecules inserted into the nanotubes are studied. As model compounds, a series of structurally related fullerenes functionalized with polyaryl groups (C(60)X, where X is a polyaryl group) of various lengths are synthesized to explore this effect. These molecules are inserted into single-walled carbon nanotubes (SWNTs) under mild conditions to prevent their decomposition and to form C(60)X@SNWT structures. The molecular chains thus formed are studied by high-resolution transmission electron microscopy, X-ray diffraction, and Raman spectroscopy, revealing that the functional groups increase the interfullerene separation proportionally with the size of X. However, the functional groups themselves appear to adopt various orientations with respect to each other and exhibit intermolecular pi-pi interactions within the cavities of the carbon nanotubes. All these effects create a distribution of observed interfullerene separations in nanotubes, which are examined by theoretical simulations and interpreted in terms of molecular geometries and intermolecular interactions.