Improved Solid Electrolyte Conductivity via Macromolecular Self-Assembly: From Linear to Star Comb-like P(S--BzMA)--POEGA Block Copolymers.

Star block copolymer electrolytes with a lithium-ion conducting phase are investigated in the present work to assess the influence of this complex architecture compared to that of the linear one, on both, bulk morphology and ionic conductivity. For that purpose, the controlled synthesis of a series of poly(styrene--benzyl methacrylate)--poly[oligo(ethylene glycol) methyl ether acrylate] [P(S--BzMA)--POEGA] block copolymers (BCPs) by reversible addition-fragmentation transfer polymerization was performed from either a monofunctional or a tetrafunctional chain transfer agent containing trithiocarbonate groups. We emphasized how a small amount of styrene (6 mol %) drastically improved the control of the RAFT polymerization of benzyl methacrylate mediated by the tetrafunctional chain transfer agent.

Electrode-modified block copoly-ionic liquid boosting the CO reduction toward CO in water-based media.

Coupling polymer and ionic liquids with electrodes for catalysis is a promising tool for optimization of electrocatalytic CO reduction reaction (CORR). Here, block copolymer ionic liquids BCPILs were synthesized controlled radical polymerization and nucleophilic post-substitution to introduce imidazole moieties. We show that, thanks to these PIL functionalities, the BCPIL/Re@HPC/GDL electrode can keep the selectivity toward CO when a higher amount of water is present in the electrolyte than the raw Re@HPC/GDL system.

Non-Covalent Integration of a [FeFe]-Hydrogenase Mimic to Multiwalled Carbon Nanotubes for Electrocatalytic Hydrogen Evolution.

Surface integration of molecular catalysts inspired from the active sites of hydrogenase enzymes represents a promising route towards developing noble metal-free and sustainable technologies for H production. Efficient and stable catalyst anchoring is a key aspect to enable this approach. Herein, we report the preparation and electrochemical characterization of an original diironhexacarbonyl complex including two pyrene groups per catalytic unit in order to allow for its smooth integration, through π-interactions, onto multiwalled carbon nanotube-based electrodes.

Review of Waterborne Organic Semiconductor Colloids for Photovoltaics.

Development of carbon neutral and sustainable energy sources should be considered as a top priority solution for the growing worldwide energy demand. Photovoltaics are a strong candidate, more specifically, organic photovoltaics (OPV), enabling the design of flexible, lightweight, semitransparent, and low-cost solar cells. However, the active layer of OPV is, for now, mainly deposited from chlorinated solvents, harmful for the environment and for human health.

A nanopatterned dual reactive surface driven by block copolymer self-assembly.

Herein, we report the selective functionalization of nano-domains obtained by the self-assembly of a polystyrene-block-poly(vinyl benzyl azide) PS-b-PVBN copolymer synthesized in three steps. First, a polystyrene macro-initiator was synthesized, and then extended with vinyl benzyl chloride by nitroxide mediated polymerization to form polystyrene-block-poly(vinyl benzyl chloride) PS-b-PVBC. Nucleophilic substitution of vinyl benzyl chloride into a vinyl benzyl azide moiety is finally performed to obtain PS-b-PVBN which self-assembled into nano-domains of vinyl benzyl azide PVBN.

Core@Corona Functional Nanoparticle-Driven Rod-Coil Diblock Copolymer Self-Assembly.

Herein, a novel strategy to overcome the influence of π-π stacking on the rod-coil copolymer organization is reported. A diblock copolymer poly(3-hexylthiophene)--poly(ethylene glycol methyl ether methacrylate) (P3HT--PEGMA) was synthesized by the Huisgen cycloaddition, so-called "click chemistry", combining the PEGMA and P3HT blocks synthesized by atom transfer radical polymerization and Kumada catalyst transfer polymerization, respectively. Using a dip-coating process, we controlled the original film organization of the diblock copolymer by the crystallization of the P3HT block via π-π stacking.

Hierarchically organized honeycomb films through block copolymer directed self-assembly in "breath figure" templating and soft microwave-triggered annealing.

Hierarchically organized polymer films are produced with a high level of order from the combination of block copolymer nanophase segregation, "breath figure" methodology and microwave irradiation. A block copolymer based on poly(methyl methacrylate) and poly(n-butylacrylate) featuring cylindrical nanopatterns is involved in the "breath figure" process to create a microporous honeycomb structure. These films are submitted to microwave annealing to enhance the degree of ordering of the nano-segregation without the destruction of the honeycomb microstructure, which is not possible by classical thermal or solvent annealing.

Crucial Role of the Electron Transport Layer and UV Light on the Open-Circuit Voltage Loss in Inverted Organic Solar Cells.

Understanding the degradation mechanisms in organic photovoltaics is crucial in order to develop stable organic semiconductors and robust device architectures. The rapid loss of efficiency, referred to as burn-in, is a major issue to be addressed. This study reports on the influence of the electron transport layer (ETLs) and UV light on the drop of open-circuit voltage (V) for P3HT:PCBM-based devices.

Hierarchical honeycomb-structured films by directed self-assembly in "breath figure" templating of ionizable "clicked" PH3T-b-PMMA diblock copolymers: an ionic group/counter-ion effect on porous polymer film morphology.

The self-assembly of 1,2,3-triazole and ionic 1,2,3-triazolium "clicked" poly(3-hexylthiophene)-b-poly(methylmethacrylate) (P3HT-b-PMMA) rod-coil diblock copolymers was used to fabricate honeycomb-patterned porous films via "breath figure" templating. The surface and inner morphologies of the honeycomb films can be both controlled by either ionizing the 1,2,3-triazole linker or changing the counter-ion nature.

Hierarchically porous bio-inspired films prepared by combining "breath figure" templating and selectively degradable block copolymer directed self-assembly.

Polymer films with hierarchical micro- and nano-porosities were prepared by combining the fast solvent evaporation "Breath Figure" (BF) method, exhibiting a highly regular honeycomb micro-porous texture, with the additional nanoscale self-assembly of polylactide-block-polystyrene (PLA-b-PS) diblock copolymers, PLA being used thereafter as a sacrificial component for nano-porosity.

Elucidation of the mechanism of redox grafting of diazotated anthraquinone.

Redox grafting of aryldiazonium salts containing redox units may be used to form exceptionally thick covalently attached conducting films, even in the micrometers range, in a controlled manner on glassy carbon and gold substrates. With the objective to investigate the mechanism of this process in detail, 1-anthraquinone (AQ) redox units were immobilized on these substrates by electroreduction of 9,10-dioxo-9,10-dihydroanthracene-1-diazonium tetrafluoroborate. Electrochemical quartz crystal microbalance was employed to follow the grafting process during a cyclic voltammetric sweep by recording the frequency change.

Redox grafting of diazotated anthraquinone as a means of forming thick conducting organic films.

Thick conductive layers containing anthraquinone moieties are covalently immobilized on gold using redox grafting of the diazonium salt of anthraquinone (i.e., 9,10-dioxo-9,10-dihydroanthracene-1-diazonium tetrafluoroborate).

Thiol-alkyne chemistry for the preparation of micelles with glycopolymer corona: dendritic surfaces versus linear glycopolymer in their ability to bind to lectins.

A poly(tert-butyl acrylate) (P(tBA)) with a glycodendric endfunctionality with eight glucose moieties was synthesised in four steps via a combination of esterification, thiol-alkyne conjugation and hetero-Diels-Alder (HDA) cycloaddition. A linear glycopolymer of similar size and composition was also synthesised in order to compare the protein binding characteristics of the polymer with glycodendritic endfunctionality to the linear glycol blockcopolymer. The two amphiphilic polymers were self-assembled in water into micelles.

Environmentally responsive particles: from superhydrophobic particle films to water-dispersible microspheres.

We describe the preparation, by precipitation copolymerization, of multifunctional divinylbenzene-co-pentafluorostyrene microspheres able to produce superhydrophobic surfaces or disperse in aqueous media upon annealing either in air or water, respectively. For that purpose, an amphiphilic block copolymer, polystyrene-b-poly(acrylic acid), was introduced in the initial feed composed of divinylbenzene and 2,3,4,5,6-pentafluorostyrene. As a result, fluorinated particles were obtained in which the diblock copolymer was encapsulated during the polymerization step.

Structured assemblies of ferromagnetic particles through covalent immobilization on functionalized polymer surfaces obtained by surface segregation.

We report a strategy to immobilize magnetic particles on polymer surfaces in an organized manner. Surface segregation of binary polymer blends provided surfaces with the desired chemical functions (carboxylic functions). These functional groups were demonstrated to be accessible and were thus able to react with magnetic particles functionalized with amine functions.