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International audience; Gaining control over supramolecular polymerization mechanisms is of high fundamental interest to understand self-assembly and self-organization processes at the nanoscale. It is also expected to significantly impact the design and improve the efficiency of advanced materials and devices. Up to now, supramolecular polymerization has been shown to take place from unimers in solution, mainly by variations of temperature or of concentration. Reported here is that supramolecular nucleation-growth of triarylamine monomers can be triggered by electrochemistry in various solvents. The involved mechanism offers new opportunities to precisely address in space and time the nucleation of supramolecular polymers at an electrode. To illustrate the potential of this methodology, supramolecular nanowires are grown an oriented over several tens of micrometers between different types of commercially available electrodes submitted to a single DC electric field, reaching a precision unprecedented in the literature.

Tris(acetylacteonate) iron(III) is a relatively ubiquitous mononuclear inorganic coordination complex. The bidentate nature of the three acetylacteonate ligands coordinating around a single centre inevitably leads to structural isomeric forms, however whether or not this relates to chirality in the solid state has been questioned in the literature. Variable temperature neutron diffraction data down to T = 3 K, highlights the dynamic nature of the ligand environment, including the motions of the hydrogen atoms. The Fourier transform of the molecular dynamics simulation based on the experimentally determined structure was shown to closely reproduce the low temperature vibrational density of states obtained using inelastic neutron scattering.

We report the preliminary results of triphenylene pyrrole hybrid molecules in an attempt to introduce self-assembled crystallinity into electroconductive polymers, in order to increase the polymer performance. However, to date, the solution state electropolymerisation has resulted in amorphous films, with no sign of crystallinity.

Conventional methods of producing carbon nanotubes are generally limited by the length and quality of the tubes and maybe more importantly, cost. This paper presents the development of solvothermal techniques designed to produce a highly scalable and cost effective method for producing carbon nanotubes in long and highly aligned bundles, without the use of transition metal catalysts. In addition, the nanotubes are prepared from feedstock materials that are otherwise persistent chemical pollutants, making the process of potential interest in environmental remediation.

We report the metal-catalyst-free production of multiwalled carbon nanotubes and nanobubbles, in a chemical reduction of hexachlorobenzene by metallic sodium, giving high yields (in excess of 80 %) and at temperatures as low as 190°C for multiwalled carbon nanotubes and 100°C for nanobubble formation. The carbon nanotube samples produced under solvothermal conditions were found to consist of large bundles of nanotubes (>50 µm) consistent with a facial growth from the surface of the molten metal. Meanwhile, the nanobubbles produced under ambient pressure were found to be small (≤1 µm), polydispersed (smallest ~50 nm), and the bulk to have a large microporous area. With the regulatory complexities and high environmental and economic costs of remediating waste containing highly hazardous halogenated aromatic chemicals, necessitating high-temperature incineration under strictly controlled conditions, this low-temperature, low-cost chemical degradation of hexachlorobenzene is of great potential as a scalable and workable remediation technology.