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In this article, a new series of conjugated polymers based on a low-cost, easily accessible vat dye called Vat orange 1 or 2,9-dibromo-dibenzo[b,def]chrysene-7,14-dione have been prepared. This compound was made electron-donating by reducing and alkylating the ketone groups into alkoxy groups, allowing the introduction of solubilizing, branched alkyl chains at the 7 and 14 positions. Polymerization reactions using Suzuki–Miyaura coupling with 6,6′-isoindigo, 3,6-di-2-thienyl-pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) and 4,7-dithieno-2,1,3-benzothiadiazole (TBT) yielded three donor–acceptor polymers with bandgap values ranging from 1.61 to 1.86 eV. Field-effect transistors (OFETs) and organic solar cells (OSCs) were fabricated and hole mobility values of up to 3.62 × 10−4 cm2 V−1 s−1 and a maximum power conversion efficiency of 1.2% were measured, respectively.

We report the successful synthesis and spectroscopic characterization of a novel, water soluble anthanthrene-based derivative, 6,12-bis(TEG)anthanthrene 3. The presence of the two long ethylene glycol side chains gives this large, six-membered polycyclic aromatic compound a high aqueous solubility. It exhibits UV–vis absorption properties similar to those of anthanthrene itself, indicating that the side chains do not have a significant effect on the electronic structure of the central chromophore. The compound exhibits strong, polarity-sensitive fluorescence in aqueous solution in the blue–green region of the spectrum, with a fluorescence quantum yield of 0.13 and a polarity sensitivity factor (PSF) of 2.0. The utility of this new fluorescent molecule as a probe of supramolecular complexation was demonstrated by its inclusion into the molecular host hydroxypropyl-β-cyclodextrin in aqueous solution. Strictly 1:1 inclusion was observed, with a moderately strong binding constant K of 650 M−1. This new fluorescence probe has significant potential applications in fluorescence-based studies of aqueous biochemical and supramolecular systems.

Wood is increasingly used in construction for the benefits it brings to occupants and for its ecological aspect. Indoor wood products are frequently subject to mechanical aggressions, their abrasion and scratch resistance thus need to be improved. The coating system ensures the wood surface protection, which is, for wood flooring, a multilayer acrylate UV-curable 100% solid system. To increase the service life of wood flooring, a new property is studied: self-healing. The objective of this study is to observe the impact of monomer structure on self-healing efficiency and the effect of self-healing parameters. A previous formulation was developed using hydrogen bond technology to generate the self-healing property. In this paper, the assessment of the formulation and the self-healing parameters’ impact on self-healing efficiency as well as the physicochemical properties are presented. The composition of the monomer part in the formulations was varied, and the effect on the conversion yield (measured by FT-IR), on the Tg and crosslinking density (measured by DMA) and on mechanical resistance (evaluated via hardness pendulum, indentation, and reverse impact) was analyzed. The self-healing efficiency of the coatings was determined by gloss and scratch depth measurements (under constant and progressive load). It was proven that monomers with three acrylate functions bring too much crosslinking, which inhibits the chain mobility necessary to observe self-healing. The presence of the AHPMA monomer in the formulation permits considerably increasing the crosslinking density (CLD) while keeping good self-healing efficiency. It was also observed that the self-healing behavior of the coatings is different according to the damage caused. Indeed, the self-healing results after abrasion and after scratch (under constant or progressive load) are different. In conclusion, it is possible to increase CLD while keeping self-healing behavior until a certain limit and with a linear monomer structure to avoid steric hindrance. Moreover, the selection of the best coatings (the one with the highest self-healing) depends on the damage.

Since the discovery of graphene in the early 2000's, polycyclic aromatic hydrocarbons (PAHs) have been resurrected and new synthetic tools have been developed to prepare unprecedented structures with unique properties. One application that has been overlooked for this class of molecules is organic solar cells (OSCs). In this account, we present the recent development in the preparation of moderate to low band gap PAHs that could potentially be used as semiconducting materials in OSCs. Our focus is directed toward all-carbon PAHs as well as their polymeric analogs.

We demonstrate the preparation of anthanthrene derivatives with fused five-membered rings. These new derivatives are prepared by a palladium catalyzed cyclopentannulation reaction from precursors derived from the low-cost dye Vat Orange 3 (4,10-dibromoanthanthrone). The new cyclopenta-anthanthrene compounds possess reduced optical and electrochemical gaps (~0.9 eV) compared to anthanthrene derivatives and are electron acceptors with lowest unoccupied molecular orbital energies of ~ -3.4 eV to -3.9 eV.

International audience; Linear and helical graphene nanoribbons (L-PyGNR and H-PyGNR) bearing electron-rich pyrrole units have been synthesized by using the photochemical cyclodehydrochlorination (CDHC) reaction. The pyrrole units in the polymer backbone make the polymer electron-rich with moderate bandgap values and relatively high HOMO energy levels. The planarization of the pyrrole unit through cyclization yields a bandgap value almost 0.5 eV lower than that measured for polypyrrole. Conductivity values in the thin film up to 0.12 S/cm were measured for the chemically oxidized L-PyGNR (four-point method). Both GNRs showed excellent fluorescence sensing properties for TNT in solution with K SV values up to 6.4 × 10 6 M −1 .

We report the synthesis of π-extended ullazine derivatives annulated with either electron-poor pyridine or electron-rich thiophene units through a metal-free, photochemical cyclodehydrochlorination (CDHC) reaction. The strongest electron-donor derivative, 7-tetradecylthieno[3′,2′:7,8]indolizino[6,5,4,3-ija]thieno[2,3-c]quinolone, was copolymerized with electron-deficient thienopyrroledione (TPD), isoindigo (IID), and diketopyrrolopyrrole (DPP) derivatives to provide three donor–acceptor conjugated polymers (D–A CPs). Their photophysical, electrochemical and photovoltaic (PV) properties were investigated. The polymers showed broad UV-vis-NIR absorption bands with λmax values of 612 nm, 698 nm, 788 nm in chloroform and exhibited optical bandgap (Eoptg) of 1.58 eV, 1.41 eV, 1.24 eV measured as films. Inverted bulk heterojunction polymer solar cells (BHJ-PSCs) were fabricated using these polymers as host and light-harvesting materials. The device based on P3:PC70BM blends shows the best power conversion efficiency (PCE) of 2.23% (Voc = 0.55 V, Jsc = 7.86 mA cm−2, FF = 52%). These promising results demonstrate that π-extended ullazine derivatives can be used as electron-rich building blocks for the construction of D–A CPs for efficient PSCs applications.

Four new copolymers based on anthanthrene for the dispersion of semiconducting SWNTs of various diameters have been synthesized. After optimization of the dispersion parameters, it has been observed that fluorene- and carbazole-based copolymers lead to a sc-SWNT enrichment with low amount of residual m-SWNTs for HiPCO nanotubes. For larger diameter Plasma torch SWNTs, phenyl-based and pyrene-based copolymers yield high concentration dispersions (0.08 mg ml−1), but no selectivity for either SWNT species. Our work opens up the use of large polycyclic aromatic hydrocarbon units such as anthanthrene derivatives for SWNT wrapping process.

Self-assembly of organic macrocycles has been exploited as a preliminary step in the synthesis of soluble and tailorable carbon-based nanostructures. Functionalized nanotubes have been prepared using, as core building blocks, nearly planar ring structures containing several alkyne units, exploiting the geometry achieved in the spontaneous preassembling step driven by π interaction. Covalent cross-linking between these units was achieved by thermal or photochemical activation with UV light. Here, we apply a moderate pressure in a sapphire anvil cell (1.0 GPa) to facilitate the preassembling and induce the cross-linking under pressure either with visible light, absorbed by two-photon absorption, or thermally. We observe a high yield of enhanced quality cross-linked nanotubes in a sample, showing, at ambient pressure, only side-chain decomposition. These results show that moderate pressures, easily achievable in large volume cells, are able to selectively favor topochemical reactions in such complex organic ...

Three new and stable diradical dications based on the 4,10-dibromoanthanthrone have been synthesized and characterized. In their dicationic state, the amines show a biradical character in the ground state. Their magnetic properties have been investigated by NMR and EPR spectroscopies. The dicationic salts shows strong and broad optical absorption in the near-infrared region. The main driving force to obtain a ground state biradical is the high steric hindrance that prevents planarization of the diphenylamines with the anthanthrone aromatic core. The radical cations are isolated in two perpendicular π-systems as demonstrated by X-ray diffraction structures. This work provides a new bridging unit in the search for biradical bis(triarylamines) salts.

Supramolecular self-assembly is an increasingly popular approach to design and prepare functional materials, for various applications such as organic electronics and sensing. Despite allowing for a precise organization of photo- and electro-active building blocks, supramolecular assemblies often show poor kinetic stability, which limits their application. Among the recent strategies developed to circumvent this issue, the covalent stabilization of supramolecular self-assembly with polydiacetylene moieties is a particularly attractive approach to well-defined nanomaterials. In this review, we present the most recent examples of covalent rigidification of supramolecualr self-assemblies through the photopolymerization of diacetylene moieties. This approach has not only shown great promise for the stabilization of supramolecular assemblies through covalent bond formation, but also showed great promise for the rational design and preparation of well-defined carbon-rich materials.

We studied structure, molecular orientation, morphology, and electrostatic properties of mixed self-assembled monolayers (SAMs) comprised of alkanethiolates (ATs) which are modified by a dipolar ester group embedded into the alkyl backbone at two different orientations, namely, with the dipole directed upward and downward from the substrate. The packing density and molecular orientation in these SAMs were found to be similar to those of the “parent” single-component monolayers. Applying X-ray photoelectron spectroscopy (XPS) as a morphology tool, we could estimate that the mixed SAMs represent homogeneous intermolecular mixtures of both components, down to the molecular level, excluding existence of “hot spots” for charge injection. The analysis of the C 1s XPS spectra and the work function data suggests that the composition of the mixed SAMs fully mimicked the mixing ratio of both components in the solutions from which these SAMs were prepared, which suggests a minor role of the dipole–dipole interaction...

Alkanethiolates (ATs) forming self-assembled monolayers (SAMs) on coinage metal and semiconductor substrates have been used successfully for decades for tailoring the properties of these surfaces. Here, we provide a detailed analysis of a highly promising class of AT-based systems, which are modified by one or more dipolar carboxylic acid ester groups embedded into the alkyl backbone. To obtain comprehensive insight, we study nine different embedded-dipole monolayers and five reference nonsubstituted SAMs. We systematically varied lengths of the alkyl segments, ester group orientations, and number of ester groups contained in the chain. To understand the structural and electronic properties of the SAMs, we employ a variety of complementary experimental techniques, namely, infrared reflection absorption spectroscopy (IRS), high-resolution X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), atomic force microscopy (AFM), and Kelvin probe (KP) AFM. These experiments are comp...

Le depistage de la trisomie 21 par les marqueurs seriques maternels repose sur un calcul de risque incluant la chaine libre de l’hormone chorionique gonadotrophique (hCGβ) et la pregnancy associated placenta protein de type A (PAPP-A). Cette etude a pour objectif de preciser les conditions pre-analytiques de stabilite de ces marqueurs en sang total a 15-25 C et dans le serum conserve a 4-8 C ; 158 patientes ont ete incluses dans l’etude. Deux techniques, Cobas 8000e602, Roche Diagnostics (58 patientes) et DelfiaXpress, PerkinElmer (100 patientes) ont ete etudiees. La stabilite des marqueurs a ete etudiee dans le sang total (15-25 C) 2, 4, 6 et 8 heures apres le prelevement et dans le serum conserve a 4-8 C a 24, 72 et 120 heures. Les variations relatives ont ete definies par le rapport (CT – C2)/C2, C2 etant la concentration du marqueur au temps 2 heures, et CT la concentration aux temps etudies. En sang total conserve 8 heures a 15-25 C, on observe une augmentation moyenne de 2,4 % pour l’hCGβ et inferieure a 1 % pour la PAPP-A. Dans le serum conserve 5 jours a 4-8 C, l’hCGβ augmente en moyenne de 4,2 % et la PAPP-A reste stable. L’impact de ces augmentations sur le calcul de risque de trisomie 21 est faible. En conclusion, des delais de conservation de 8 heures du sang total a 15-25 C et de 5 jours apres centrifugation et separation du serum (gel separateur ou decantation) et conservation a 4-8 C peuvent etre consideres comme acceptables.

Singlet and triplet excited‐state dynamics of anthanthrene and anthanthrone derivatives in solution are studied. Triisopropylsilyl‐ (TIPS) or H‐terminated ethynyl groups are used to tune the singlet and triplet energies to enable their potential applications in singlet fission and triplet fusion processes. Time‐resolved optical and electron paramagnetic resonance (EPR) spectroscopies are used to obtain a mechanistic understanding of triplet formation. The anthanthrene derivatives form triplet states efficiently at a rate (ca. 107 s−1) comparable to radiative singlet fluorescence processes with approximately 30 % triplet yields, despite their large S1‐T1 energy gap (>1 eV) and the lack of carbonyl groups. In contrast, anthanthrone has a higher triplet yield (50±10 %) with a faster intersystem crossing rate (2.7urn:x-wiley:21926506:media:cplu201900410:cplu201900410-math-0001 108 s−1) because of the n‐π* character of the S1←S0 transition. Analysis of time‐resolved spin‐polarized EPR spectra of these compounds reveals that the triplet states are primarily generated by the spin‐orbit‐induced intersystem crossing mechanism. However, at high concentrations, the EPR spectrum of the 4,6,10,14‐tetrakis(TIPS‐ethynyl) anthanthrene triplet state shows a significant contribution from a non‐Boltzmann population of the ms=0 spin sublevel, which is characteristic of triplet formation by singlet fission.

The solution-phase synthesis is one of the most promising strategies for the preparation of well-defined graphene nanoribbons (GNRs) in large scale. To prepare high quality, defect-free GNRs, cycloaromatization reactions need to be very efficient, proceed without side reaction and mild enough to accommodate the presence of various functional groups. In this Minireview, we present the latest synthetic approaches for the synthesis of GNRs and related structures, including alkyne benzannulation, photochemical cyclodehydrohalogenation, Mallory and Pd- and Ni-catalyzed reactions.

Polycyclic aromatic hydrocarbons (PAHs) are interesting building blocks for the preparation of conjugated polymers due to their extended π surface and planar conformation. However, their use as comonomer in conjugated polymers often leads to nonplanar main chains as a consequence of high steric hindrance at the linking point. Herein, we report the synthesis of a ladderized anthanthrene unit using an sp3 carbon bridge. Three conjugated copolymers with fluorene, isoindigo, and bithiophene derivatives have been synthesized and characterized to study the effect of such ladderization on the electronic properties. The dihedral angle between the ladderized anthanthrene and adjacent units has been significantly reduced by the formation of the sp3 carbon bridge, thus eliminating the steric hindrance with the proton at the peri position of the anthanthrene unit and red-shifting the absorption spectrum by 25 nm.

Organic-based nanoparticles hold great potential for optoelectronics and biomedicine as they may provide optical properties in the visible range and notable advantages over inorganic counterparts. In this report, we exploit aggregation-induced emission (AIE) from the well-known tetraphenylethene (TPE) to yield photoluminescent polymer particles by a dispersion polymerization route. 1,1-Bis(4-ethynylphenyl)-2,2-diphenylethene is polymerized by a Glaser-type dispersion polymerization, providing nanoparticles of 170–600 nm with low polydispersity by simply varying monomer loadings. Optical characterization reveals emission bands at 500 nm and 600 nm, where UV irradiation of the particles causes the 500 nm band to increase relative to the 600 nm one. Structural characterization by 13C MAS-NMR allows confirming that this change upon UV irradiation is not induced by a chemical modification, thus suggesting a physical change in the particle's morphology. Altogether, the results of this work allow enlarging the library of TPE-comprising particles, but also enhance the variety of particles synthesized from Glaser-type dispersion polymerization. The study also allows gaining insight into the photochemical stability of TPE-containing particles, where the non-destructive UV irradiation lets us plan the development of new polyyne/TPE hybrid systems.

A new alkyne-based macrocycle that combines monoyne, diyne and tetrayne is reported. Despite its unusual trapezoid shape, the bending of the tetrayne unit allows the macrocycle to be unstrained. The macrocycle is synthesized by a combination of selective deprotection of silylated alkyne, Castro–Stephen–Sonogashira coupling and copper-mediated oxidative homocoupling. The final intramolecular cyclization proceeded in surprisingly high yield (72%) using modified Eglinton conditions in moderate dilution.

The two-dimensional (2D) surface-directed self-assembly of dibenzonitrile diacetylene (DBDA) on Ag(111) under ultrahigh vacuum (UHV) conditions was investigated by combining scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS) and theoretical simulations based on density functional theory (DFT) calculations. The molecule consists of two benzonitrile groups (–C6H4–CN) on each side of a diacetylene (–CC–CC–) backbone. The terminating nitrile (–CN) groups at the meta position of the phenyl rings lead to cis and trans stereoisomers. The trans isomer is prochiral and can adsorb in the R or S configuration, leading to the formation of enantiomeric self-assembled networks on the surface. We identify two simultaneously present supramolecular networks, termed parallel and chevron phases, as well as a less frequently observed butterfly phase. These networks are formed from pure R (or S) domains, racemic mixtures (RS), and cis isomers, respectively. Our complementary data illustrates that the formation of the 2D supramolecular networks is driven by intermolecular hydrogen bonding between nitrile and phenyl groups (–CN⋯H–C6H3). This study illustrates that the molecular arrangement of each network depends on the geometry of the isomers. The orientation of the nitrile group controls the formation of the most energetically stable network via intermolecular hydrogen bonding.

This review presents an overview of the recent developments in the area of vat dye chemistry for the preparation of π-conjugated molecules and polymers for organic electronic applications. Vat dyes are well-established molecules in the textile colouring and painting industry as they are inexpensive and highly stable. Their optical properties in the visible region are attributed to their highly conjugated sp2 carbon networks and the presence of functional groups, especially ketones that allow the formation of “leuco” species. In this review, we will show how the presence of functional groups on these highly conjugated scaffolds can be used to modify their electronic and optical properties to make them useful building blocks for semiconducting organic materials.

There is a strong clinical need to develop small-caliber tissue-engineered blood vessels for arterial bypass surgeries. Such substitutes can be engineered using the self-assembly approach in which cells produce their own extracellular matrix (ECM), creating a robust vessel without exogenous material. However, this approach is currently limited to the production of flat sheets that need to be further rolled into the final desired tubular shape. In this study, human fibroblasts and smooth muscle cells were seeded directly on UV-C-treated cylindrical polyethylene terephthalate glycol-modified (PETG) mandrels of 4.8 mm diameter. UV-C treatment induced surface modification, confirmed by Fourier-transform infrared spectroscopy (FTIR) analysis, was necessary to ensure proper cellular attachment and optimized ECM secretion/assembly. This novel approach generated solid tubular conduits with high level of cohesion between concentric cellular layers and enhanced cell-driven circumferential alignment that can be manipulated after 21 days of culture. This simple and cost-effective mandrel-seeded approach also allowed for endothelialization of the construct and the production of perfusable trilayered tissue-engineered blood vessels with a closed lumen. This study lays the foundation for a broad field of possible applications enabling custom-made reconstructed tissues of specialized shapes using a surface treated 3D structure as a template for tissue engineering.

Seven π-extended derivatives of the known tetraphenylethylene (TPE) have been studied for their aggregation-induced emission properties. Modulation of the emission properties of these anthanthrone-based luminogens has been accomplished through simple chemical modifications on four different positions of the anthanthrone core. The optical properties, along with X-ray diffraction and DFT-optimized structures, were studied. This work provides a new, easily accessible bridging unit for the TPE framework with a red-shifted emission.

Novel nanographenes were prepared by a photochemical cyclodehydrochlorination (CDHC) reaction. Chlorinated precursors were irradiated in acetone in the presence of a base or in pure benzene and underwent multiple (up to four) regioselective cyclization reactions to provide rigid π-conjugated molecules. Pure compounds were recovered in good yields by simple filtration at the end of the reaction. The CDHC reaction showed compatibility with both electron-poor and electron-rich substrates, thus allowing the synthesis of pyridine- and thiophene-fused nanographenes. It also enabled the synthesis of sterically hindered contorted π-conjugated molecules without causing full aromatization. A kinetic study showed that the CDHC reaction under the conditions used is a very fast process, and some reactions are completed within minutes. The CDHC reaction thus shows great potential as an alternative to other reactions involving harsher conditions for the preparation of nanographenes.

Five new copolymers based on the anthanthrone moiety were synthesized using Stille coupling. The anthanthrone unit was coupled with two electron-rich units (thiophene and carbazole) and three electron-poor units (thienopyrroledione, diketopyrrolopyrrole, and benzothiadiazole). The optoelectronics properties of the polymers were investigated and suggest that the anthanthrone moiety dictates the electronic properties of the materials with little regards to the nature of the comonomers. Fluoride-promoted photoinduced electron transfer on anthanthrone derivatives yielded to radical anion species that can be reversibly oxidized to the neutral form by exposure to air.

Rhomboidal macrocyclic subunits of graphdiyne-like nanoribbon (GDNR) bearing both alkyne and diyne units, allowing for multichannel π-conjugation, were synthesized using an oxidative Glaser-type ring closing reaction. These subunits, called the "meshes" of the nanoribbon, possess phenyl groups with decyloxy solubilizing chains on each corner. The yields of the ring closing reaction highly depend on the metal (Cu or Pd) catalyst used for the macrocyclization step. Increasing the width of the meshes from one macrocycle to two fused macrocycles resulted in a decrease of the bandgap by 0.23 eV as shown by optical spectroscopy. The optimized geometries of the meshes alongside their HOMO and LUMO orbitals were calculated using DFT calculations at the B3LYP/6-31+G** level of theory. The results showed a nearly planar conformation for both meshes with HOMO and LUMO orbitals entirely delocalized over the molecules.

Dendrimers are monodisperse polymers grown in a fractal manner from a central point. They are poised to become the cornerstone of nanoscale devices in several fields, ranging from biomedicine to light-harvesting. Technical difficulties in obtaining these molecules has slowed their transfer from academia to industry. In 2001, the arrival of the “click chemistry” concept gave the field a major boost. The flagship reaction, a modified Hüisgen cycloaddition, allowed researchers greater freedom in designing and building dendrimers. In the last five years, advances in click chemistry saw a wider use of other click reactions and a notable increase in the complexity of the reported structures. This review covers key developments in the click chemistry field applied to dendrimer synthesis from 2010 to 2015. Even though this is an expert review, basic notions and references have been included to help newcomers to the field.

With the intent of generating metallocavitands isostructural to species [(CpZr)3(μ(3)-O)(μ(2)-OH)3(κO,O,μ(2)-O2C(R))3](+), the reaction of Cp*2ZrCl2 and Cp*ZrCl3 with phenylcarboxylic acids was carried out. Depending on the reaction conditions, five new complexes were obtained, which consisted of Cp*2ZrCl(κ(2)-OOCPh) (1), (Cp*ZrCl(κ(2)-OOCPh))2(μ-κ(2)-OOCPh)2 (2), [(Cp*Zr(κ(2)-OOCPh))2(μ-κ(2)-OOCPh)2(μ(2)-OH)2]·Et2O (3·Et2O), [[Cp*ZrCl2](μ-Cl)(μ-OH)(μ-O2CC6H5)[Cp*Zr]]2(μ-O2CC6H5)2 (4), and [Cp*ZrCl4][(Cp*Zr)3(κ2-OOC(C6H4Br)3(μ3-O)(μ2-Cl)2(μ2-OH)] [5](+)[Cp*ZrCl4](-). The structural characterization of the five complexes was carried out. Species 3·Et2O exhibits host-guest properties where the diethyl ether molecule is included in a cavity formed by two carboxylate moieties. The secondary interactions between the cavity and the diethyl ether molecule affect the structural parameters of the complex, as demonstrated be the comparison of the density functional theory models for 3 and 3·Et2O. Species 5 was shown to be isostructural to the [(CpZr)3(μ(3)-O)(μ(2)-OH)3(κO,O,μ(2)-O2C(R))3](+) metallocavitands.

Anthanthrene small molecules with different pendant groups were investigated as semiconductors for organic field-effect transistors and solar cells. Field-effect mobilities were greatly improved with solvent annealing and reached maximum values of 0.078 cm2 V−1 s−1 for a thiophene-appended anthanthrene derivative. When used as donors in conjunction with PC61BM in bulk heterojunction solar cells, a maximum PCE of 2.4% was achieved with good Voc and FF of 0.77 V and 59%, respectively. Although solvent annealing induced J-aggregation of all anthanthrene compounds, such processing step did not necessarily improved the solar cell J–V characteristics as opposed to the field effect mobility. The results showcase the potential of the polycyclic anthanthrene core as a building block for organic electronics.

Six anthanthrene-based conjugated polymers with either electron-rich or electron-poor units were synthesized and characterized. All polymers exhibit optical absorption in the visible region owing to their extended conjugation. Experimental data and computational results indicate that the comonomer attached to the anthanthrene unit has only little effect on the electronic properties of the polymers.

Narrow thiophene-edged graphene nanoribbons (GNRs) were prepared from polychlorinated thiophene-containing poly(p-phenylene)s using the photochemical, metal-free cyclodehydrochlorination (CDHC) reaction. 1 H NMR and Raman spectroscopy confirmed the structures of the GNRs. The regioselectivity of the CDHC reaction allows the preparation of both laterally symmetrical and unsymmetrical GNRs and, consequently, the modulation of their optical and electronic properties.

New anthanthrone-based polycyclic scaffolds possessing peripheral crowed quinodimethanes have been prepared. While the compounds adopt a closed-shell butterfly shaped structure in the ground state, a concave-to-convex fluxional dynamic inversion is accessible with a low energy barrier through an open-shell diradicaloid transition-state. Mainly driven by the release of strainattributed to the steric hindrance at the peri position of the anthanthrone core, a low-lying open-shell diradical is accessible through planarization of the core, which can be achieved by thermal excitation in solution. Alternatively, planarization can be achieved by application of mild pressure in the solid state, in which case the diradical remains kinetically trapped in an excited open-shellconfiguration. Cross-information from quantum chemistry, Ramanspectroscopy and magnetic experiments allow us to corroborate thesehypotheses and determine that the resulting nanographene-likestructure possess unpaired electrons mainly localized at the exoanthanthrenecarbons bearing phenyl substituents.

The design of advanced new generation conjugated materials with improved properties for photovoltaic applications has been the focus of research in recent years. This work reports on novel anthanthrone/anthracene and anthanthrene/anthracene co-polymers as p-type conjugated semiconductors in organic photovoltaics. The presence of anthracene component with the grafted alkyloxy chains enhanced the solubility and process-ability of the co-polymers. The photophysical and photovoltaic parameters greatly depend on ratio of components of the co-polymers and nature of the grafted chains. Devices using the blends of SV15 and PCBM in 1:2 ratio gave $J_{\mathrm{s}\mathrm{c}}$ 3.97 mA/cm2 and higb $V_{oc}$ 0.92 V with efficiency 1.7%.

Carbon nanoparticles (CNPs) are promising materials for optoelectronic and biomedical applications thanks to their optical properties, low production cost, and superior biocompatibility compared to traditional semiconductor quantum dots. The countless synthetic methods reported allow a library of diverse CNP structures and optical properties, guiding their subsequent applications. However, the current drawbacks lie mainly within these synthetic processes, as many of them require harsh conditions preventing control over morphology and often generating chemically inert nanoparticles. Thus, more advances on low temperature and controllable synthetic processes are desirable. In this study, we suggest a new strategy to synthesize CNPs with tunable size, while avoiding the use of harsh conditions and allowing easy surface functionalization. The metastable state of polyyne-containing materials appoints them as ideal precursors for low-temperature preparation of carbon-rich structures. Our approach is to synthesize octatetrayne-containing particles prompt to spontaneous reaction, including topochemical polymerization, followed by aromatization, to avoid harsh carbonization steps. For the particle synthesis, the well-known dispersion polymerization process has been adapted for homocoupling of terminal butadiynes, generating the octatetrayne-containing particles. The method was proven reproducible, scalable, and versatile, as the particles' size can be modulated between 50 and 170 nm. Surface functionalization via thiol-yne click chemistry was completed with a pyrene-modified thiol ligand to provide the CNPs with photoactive properties in the visible range. The functionalized particles exhibit fluorescence at 470 nm arising from excimer formation.

The synthesis and self-assembly of two new phenylacetylene macrocycle (PAM) organogelators were performed. Polar 2-hydroxyethoxy side chains were incorporated in the inner part of the macrocycles to modify the assembly mode in the gel state. With this modification, it was possible to increase the reactivity of the macrocycles in the xerogel state to form polydiacetylenes (PDAs), leading to a significant enhancement of the polymerization yields. The organogels and the PDAs were characterized using Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM).

A series of ferrocene-based statistical copolymers have been prepared via radical polymerization and their nanoporous structure was characterized using inert gas adsorption–desorption isotherms and high resolution transmission electron microscopy (HRTEM). The porosity parameters of the polymers were obtained by physisorption isotherms (N 2 at −196 °C, Ar at −186 °C) and modern quenched solid density functional theory (QSDFT) methods were implemented for an advanced analysis of the polymeric materials. The materials show both microporosity and mesoporosity with relatively high surface area and pore volume, which are retained upon the incorporation of ferrocene units to the polymer backbone. The hydrogen storage capability of those polymers was also tested. The introduction of ferrocene units within the polymer structure contributed to an increase of the hydrogen adsorption ability of the porous polymers compared to their ferrocene-free equivalents.

An efficient and versatile synthetic strategy toward cruciform anthanthrene compounds using Sonogashira couplings steps was developed. Acetylenic linkers were used to effectively extend the π-conjugation of polycyclic anthanthrone and anthanthrene compounds and tune their optoelectronic properties. Structure-property relationships supported by DFT calculations indicated more effective π-conjugation along the 6,12 axis than along the 4,10 axis. These molecules displayed strong J-aggregation both in solution and in the solid state and proved to be highly photostable with reversible redox processes, which are properties of interest in materials sciences.

This report describes the design and development of functionalized silica particles using tethered Schiff base ligands for uranium extraction from rare earth element leach liquors. We evaluated different grafting approaches (both one- and two-sided tethering); and found the maximum U(VI) adsorption capacity for the functionalized silica was 95 ± 2 mg g −1 . The functionalized particles demonstrated a very high degree of affinity for the uranyl and thorium ions with K d values at pH 6 exceeding 19,000 and 900,000 mL g −1 , respectively. This selectivity for these ions is better than most metal ions present in leach liquors, and the extraction kinetics are faster than pure Schiff base crystals. The Schiff-base-functionalized silica particles also exhibited a high degree of reusability over five cycles of loading-elution in the conditions tested.

The preparation of carbon nanomaterials has been the focus of many research groups over the last twenty years. Traditionally, the synthesis of these materials has been accomplished using physical methods involving harsh conditions, limiting their applicability in numerous technological areas. Thus, researchers have been constantly working on developing new methods involving organic molecules possessing highly reactive functional groups that can be graphitized under mild conditions. In this tutorial review, we highlight recent approaches for the preparation of various carbon nanomaterials using physical stimuli (heat and/or light) to trigger graphitization of both non-organized and self-assembled molecular precursors. Special attention is devoted to the preparation of carbon nanomaterials from alkyne-containing molecules.

Since the aggregation-induced emission (AIE) phenomenon is very sensitive to steric hindrance, we set out to use it as a tool to probe the periphery of dendrimers. To achieve this, dendrimers with an ethylene oxide (EO) core were synthesized and then decorated with AIE-active units. Tetraphenylethylene (TPE) with varying spacer lengths was used as the AIE decoration to create two parallel series of these dendrimers up to generation four. Systematic photoluminescence studies demonstrated that peripheral crowding starts at G3. Further analysis showed that the AIE technique is sensitive enough to distinguish small differences in architecture. When used in combination with dynamic light scattering, our AIE strategy revealed a complex relationship between the aggregates’ size and their emission.

Rational design of meta-linked oligophenylbutadiynylene (OPBD) derivatives was conducted in order to gain insight into their gelation properties and reactivity toward topochemical polymerization to yield polydiacetylenes (PDAs). Different structural parameters influencing the gel formation such as the presence of peripheral 2-hydroxyethoxy side chains and the position of amide functionalities, responsible for intermolecular hydrogen bonds, were studied. Topochemical polymerization of butadiyne units contained within the OPBDs was performed and the resulting PDAs were characterized by electron microscopy and spectroscopy.

A series of 6,12-bis(amino) anthanthrene-based conjugated molecules were prepared and characterized using UV-vis and fluorescence spectroscopy and cyclic voltammetry. The absorption spectra and redox potentials of these molecules can be modulated by changing the conjugated moieties linked at the 4 and 10 positions. Moreover, the optoelectronic properties of these derivatives strongly depend on the moieties attached to the nitrogen atoms at the 6 and 12 positions.

Carbon nanomaterials have been the subject of intense research over the past 20 years. Both the physical and all-organic methods used to prepare them possess advantages and drawbacks regarding purity, batch-to-batch uniformity, large-scale production, and conditions of preparation. In this account, we present an overview of ‘hybrid methods’, in which well-defined, reactive organic precursors based on alkynes are self-assembled and transformed using physical stimuli to produce carbon nanomaterials with different sizes, shapes, and functions. 1 Introduction 2 Topochemical Polymerization of [n]Yne Derivatives 2.1 Topochemical Polymerization of 1,4-Diarylbutadiyne Derivatives in the Gel and Xerogel States 2.2 Carbon-Rich Nanowires and Nanotubes 3 Conclusion

A star-shaped molecule with three butadiyne moieties attached to a central phenyl core was self-assembled via organogel formation in different solvents and subjected to UV irradiation in its xerogels form to give a soluble conjugated 1D nanowire made of three connected polydiacetylene (PDA) chains. The resulting polymer has a slightly lower optical band gap than its linear counterpart and presents no chromism property, indicative of the rigid nature of the polymer thus obtained.

Soluble organic nanorods were prepared from phenylacetylene macrocycles using the topochemical polymerization of butadiyne moieties placed both inside and outside the macrocycles' skeletons. Macrocycles containing amide groups were self-assembled in a columnar fashion through the formation of an organogel in ethyl acetate. Upon irradiation with UV light, the Raman signals associated with butadiyne units completely vanished, indicating the creation of covalently linked nanorods.