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The synthesis of O‐doped polyaromatic hydro‐ carbons in which two polycyclic aromatic hydrocarbon sub units are bridged through one or two O atoms has been achieved. This includes high‐yield ring‐closure key steps that, depending on the reaction conditions, result in the formation of furanyl or pyranopyranyl linkages through intramolecular C−O bond formation. Comprehensive photophysical measurements in solution showed that these compounds have exceptionally high emission yields and tunable absorption properties throughout the UV/Vis spectral region. Electrochemical investigations showed that in all cases O annulation increases the electron‐donor capabilities by raising the HOMO energy level, whereas the LUMO energy level is less affected. Moreover, third‐order nonlinear optical (NLO) measurements on solutions or thin films containing the dyes showed very good values of the second hyperpolarizability. Importantly, poly(methyl methacrylate) films containing the pyranopyranyl derivatives exhibited weak linear absorption and NLO absorption compared to the nonlinearity and NLO refraction, respectively, and thus revealed them to be exceptional organic materials for photonic devices.

The self-assembly and self-organization behavior of uracil-conjugated enantiopure (R)- or (S)-1,1′-binaphthyl-2,2′-diol (BINOL) and a hydrophobic oligo(p-phenylene ethynylene) (OPE) chromophore exposing 2,6-di(acetylamino)-pyridine termini are reported. Systematic spectroscopic (UV-vis, CD, fluorescence, NMR, and SAXS) and microscopic studies (TEM and AFM) showed that BINOL and OPE compounds undergo triple H-bonding recognition, generating different organic nanostructures in solution. Depending on the solvophobic properties of the liquid media (toluene, CHCl3, CHCl3/CHX, and CHX/THF), spherical, rod-like, fibrous, and helical morphologies were obtained, with the latter being the only nanostructures expressing chirality at the microscopic level. SAXS analysis combined with molecular modeling simulations showed that the helical superstructures are composed of dimeric double-cable tape-like structures that, in turn, are supercoiled at the microscale. This behavior is interpreted as a consequence of an interplay among the degree of association of the H-bonded recognition, the vapor pressure of the solvent, and the solvophobic/solvophilic character of the supramolecular adducts in the different solutions under static and dynamic conditions, namely solvent evaporation conditions at room temperature. (Chemical Equation Presented).

The covalent functionalization of (7, 6)-enriched single-walled carbon nanotubes (SWCNTs) with oligophenylenevinylene (OPV) moieties terminating with a dimethylamino group is proposed as an efficient way to enhance the affinity of CNTs with Spiro-MeOTAD in perovskite-based solar cells. The evidence of SWCNTs functionalization and the degree of OPV substitution on SWCNTs are established from TGA, XPS, TEM and Raman techniques. Our tailored doping materials display photovoltaic performances in line with conventional Li-doped spiro-MeOTAD system, showing at the same time a significantly improved chemical stability of the perovskite component over time. Furthermore, the comparison of the photovoltaic performances with those obtained with non-functionalized SWCNTs clearly suggest that the presence of the organic appends ensures highly reproducible PV performances. Our results demonstrate the suitability of this material as a valid doping agent for spiro-MeOTAD, representing a viable alternative to the conventional Li-salt.

The preparation of the first soluble quaterrylene derivative featuring peripheral tert-butyl substituents and sterically hindering, core-anchored triflate groups has been achieved. This involves a facile synthetic route based on an oxidative coupling of perylene precursors in the presence of H2O2 as oxidant. The steric hindrance between the OTf substituents at the central bay position of the quaterrylene board triggers a strong deformation of the central perylene planarity, which forces the quaterrylene platform to adopt a twisted geometry as shown by X-Ray analysis. Exceptionally, photophysical investigations show that the core-twisted quaterrylene phosphoresces in the NIR spectral region at 1716 nm. Moreover, third-order nonlinear optical (NLO) measurments on solutions and thin film containing the relevant molecule showed very large second hyperpolarizability values, as predicted by theoretical calculations at the CAM-B3LYP/6-31G** level of theory, making this material very appealing for photonic applications. This article is protected by copyright. All rights reserved.