A5002194799- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Molecular Junctions and Nanostructures
- Mass Spectrometry Techniques and Applications
- Organic Light-Emitting Diodes Research
- Photochemistry and Electron Transfer Studies
- Porphyrin and Phthalocyanine Chemistry
- Analytical Chemistry and Chromatography
- Crystallography and molecular interactions
- Carbon dioxide utilization in catalysis
- Perovskite Materials and Applications
- Luminescence and Fluorescent Materials
- biodegradable polymer synthesis and properties
- Photochromic and Fluorescence Chemistry
- Organic and Molecular Conductors Research
- Liquid Crystal Research Advancements
- Advanced Memory and Neural Computing
- Synthesis and Properties of Aromatic Compounds
- Supramolecular Chemistry and Complexes
- Advanced Sensor and Energy Harvesting Materials
- Polymer composites and self-healing
- Chemical Synthesis and Analysis
- Analytical chemistry methods development
University of Mons
2016-2025
Novel (United States)
2014-2021
Center for Innovation
2017-2018
Material (Belgium)
2015-2018
Materia (United States)
2015
Materia Nova
2015
Université Libre de Bruxelles
2004-2013
Université Nantes Angers Le Mans
2013
Institut des Sciences et Technologies Moléculaires d'Angers
2013
Université d'Angers
2013
We describe at the quantum-chemical level main parameters that control charge transport molecular scale in discotic liquid crystals. The focus is on stacks made of triphenylene, hexaazatriphenylene, hexaazatrinaphthylene, and hexabenzocoronene molecules derivatives thereof. It found a subtle interplay between chemical structure their relative positions within determines properties; features required to promote high mobilities materials are established basis calculated structure−property...
Abstract Unlike conventional thermally activated delayed fluorescence chromophores, boron-centered azatriangulene-like molecules combine a small excited-state singlet-triplet energy gap with high oscillator strengths and minor reorganization energies. Here, using highly correlated quantum-chemical calculations, we report this is driven by short-range of the electron density taking place upon electronic excitation these multi-resonant structures. Based on finding, design series π-extended...
Polyphenols (synthetically modified or directly provided by human diet) scavenge free radicals H-atom transfer and may thus decrease noxious effects due to oxidative stress. Free radical scavenging polyphenols has been widely theoretically studied from the thermodynamic point of view whereas kinetic much less addressed. The present study describes kinetic-based structure–activity relationship for quercetin. This compound is very characteristic wide flavonoid subclass polyphenols. a mechanism...
The structural organization of three different families semicrystalline π‐conjugated polymers is reported (poly(3‐hexylthiophene) (P3HT), poly[2,6‐(4,4‐bis‐alkyl‐4H‐cyclopenta‐[2,1‐b;3,4‐b0]‐dithiophene)‐ alt ‐4,7‐(2,1,3‐benzothiadiazole)](cyclopentadithiophene‐benzothiadiazole) (CDT‐BTZ) and poly(N,N"‐bis‐2‐octyldodecylnaphtalene‐1,4,5,8‐bis‐dicarboximide‐2,6‐diyl‐ ‐5,5–2,2‐bithiophene (P(NDI2OD‐T2))). These have triggered significant interest for their remarkable charge‐transport...
Molecular doping-the use of redox-active small molecules as dopants for organic semiconductors-has seen a surge in research interest driven by emerging applications sensing, bioelectronics, and thermoelectrics. However, molecular doping carries with it several intrinsic problems stemming directly from the character these materials. A recent breakthrough was technique based on ion-exchange, which separates redox charge compensation steps process. Here, equilibrium kinetics ion exchange model...
Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of dopant counterions. Here, we present a combined experimental theoretical study rebutting this belief. Using newly developed doping technique based on ion exchange, prepare highly doped films with several...
The poor operational stability of non-fullerene electron acceptor (NFA) organic solar cells (OSCs) currently limits their commercial application. While previous studies have primarily focused on the degradation NFA component, we also consider here donor material. We examine three representative polymers, PM6, D18, and PTQ10, paired with benchmark NFA, Y6. After light soaking PM6 D18 in air, find an enhanced conversion singlet excitons into trapped interchain polaron pairs sub-100 femtosecond...
This work focuses on two fundamental processes in organic solar cells-exciton dissociation and charge recombination-and describes how quantum-chemical calculations can be exploited to estimate the molecular parameters that determine rates of these processes. The general concepts behind our approach are illustrated by considering a donor-acceptor complex made phthalocyanine (electron donor) molecule perylene (acceptor) molecule. results highlight relative depend dimensionality molecules,...
A new series of cationic blue-emitting, heteroleptic iridium(III)-based metal complexes were systematically synthesized using two 4,6-difluorophenylpyridine ligands as well one methyl- or n-butyl-substituted bisimidazolium salt carbene-type ligand. In degassed CH2Cl2, all display highly efficient, blue phosphorescence (λmax ∼ 452 nm; emission quantum yield 0.30) at room temperature and also show in a thin film. The measured photophysical properties the have been rationalized with help...
Polymeric semiconductors are materials where unique optical and electronic properties often originate from a tailored chemical structure. This allows for synthesizing conjugated macromolecules with ad hoc functionalities organic electronics. In photovoltaics, donor-acceptor co-polymers, moieties of different electron affinity alternating on the chain, have attracted considerable interest. The low bandgap offers optimal light-harvesting characteristics has inspired work towards record power...
Synthetic control of the mutual arrangement cyclometalated ligands (C^N) in Ir(III) dimers, [Ir(C^N)(2)Cl](2), and cationic bis-cyclometalated complexes, [Ir(C^N)(2)(L^L)](+) (L^L = neutral ligand), is described for first time. Using 1-benzyl-4-(2,4-difluorophenyl)-1H-1,2,3-triazole (HdfptrBz) as a cyclometalating ligand, two different [Ir(dfptrBz)(2)Cl](2), are synthesized depending on reaction conditions. At 80 °C, dimer with an unusual cis-C,C cis-N,N configuration C^N isolated. In...
Hexaazatrinaphthylene (HATNA) derivatives with six alkylsulfanyl chains of different length (hexyl, octyl, decyl and dodecyl) have been designed to obtain new potential electron-carrier materials. The electron-deficient nature these compounds has demonstrated by cyclic voltammetry. Their thermotropic behaviour studied means differential scanning calorimetry polarised optical microscopy. supramolecular organisation discotic molecules explored temperature-dependent X-ray diffraction on powders...
A series of bulky end-capped [1]benzothieno[3,2-b]benzothiophenes (BTBTs) are developed in order to tune the packing structure via terminal substitution. coupled theoretical and experimental study allows us identify 2,7-di-tert-butylBTBT as a new high-performance organic semiconductor with large well-balanced transfer integrals, evidenced by quantum-chemical calculations. Single-crystal field-effect transistors show remarkable average saturation mobility 7.1 cm2 V−1 s−1.
We present a Monte Carlo approach to estimate how molecular parameters impact hopping rates and charge mobilities in organic pi-conjugated materials. Our goal is help establishing structure-properties relationships. As first step, our illustrated by considering model system made of one-dimensional array pentacene molecules; we describe the variations electron-transfer resulting as function electric field presence disorder traps. The results highlight that there no direct relationship between...
The structural and electronic properties of four isomers didodecyl[1]-benzothieno[3,2-b][1]benzothiophene (C12-BTBT) have been investigated. Results show the strong impact molecular packing on charge carrier transport polarization properties. Field-induced time-resolved microwave conductivity measurements unravel an unprecedented high average interfacial mobility 170 cm2 V−1 s−1 for 2,7-isomer, holding great promise field organic electronics. Since dawn electronics in 1970's, academic...
Abstract Charge carrier mobility is a central property that characterizes the performances of organic semiconductors and mostly measured in field‐effect transistors. High values are sought by many research teams. This article, provides an overview best performing molecular constructed on question: What currently limits charge crystals semiconductors? With this mind, we confront, critical way, current theoretical understanding to most salient experimental results with hope reach deeper based...
Despite offering robust mechanical properties, polymer networks suffer from a lack of recyclability, reshaping, and healability. Designing stiff remendable that can repair under mild conditions remains challenge to extend their field applications. Herein, we describe simple approach design nonisocyanate-based polyurethane network featuring multiresponsiveness (to humidity temperature) outstanding healing as obtained by combining iminoboronate boroxine chemistry. In spite the presence...
Abstract Efficient conjugated polymer optoelectronic devices benefit from concomitantly high luminescence and charge carrier mobility. This is difficult to achieve, as interchain interactions, which are needed ensure efficient transport, tend also reduce radiative recombination lead solid-state quenching effects. Many studies detail strategies for reducing these interactions increase luminescence, or modifying chain packing motifs improve percolation transport; however achieving properties...
Discotic liquid crystals have emerged as very attractive organic semiconductors due to their high degree of ordering and self-healing capacity. Quantum-chemical calculations that describe the main parameters governing charge-transfer processes in these systems at molecular level are reported. The concepts illustrated by considering columns made triphenylene molecules derivatives (see Figure).
We report a detailed quantum-chemical characterization of the electronic and optical properties polyfluorene chains compare them to those in copolymers containing alternating fluorene benzothiadiazole or ethylenedioxythiophene units. The introduction comonomer can strongly modify excitonic as well efficiency charge- energy-transfer processes. choice is thus critical targeting specific while maintaining good transport properties.
Discotic liquid crystals emerge as very attractive materials for organic-based (opto)electronics they allow efficient charge and energy transport along self-organized molecular columns. Here, angle-resolved photoelectron spectroscopy (ARUPS) is used to investigate the electronic structure supramolecular organization of discotic molecule, hexakis(hexylthio)diquinoxalino[2,3-a:2',3'-c]phenazine, deposited on graphite. The ARUPS data reveal significant changes in properties when going from...
Molecular modeling shows that longitudinal displacement of the backbones by a couple ångströms has profound impact on electronic coupling mediating charge transport in conjugated copolymer. These changes can be probed monitoring calculated X-ray scattering patterns and NMR chemical shifts as function sliding polymer chains comparing them to experiment.
A series of blue and blue-green emitters based on neutral bis- tris-cyclometalated Ir(III) complexes with 1-benzyl-4-(2,6-difluorophenyl)-1H-1,2,3-triazole (dfptrBn) as cyclometalating ligand is reported. The bis-cyclometalated the type [Ir(dfptrBn)2(L∧X)] different ancillary ligands, L∧X = picolinate (pic) (2) or 2-(5-(perfluorophenyl)-2H-1,2,4-triazol-3-yl)pyridine (pytrF5) (3), are described their photophysical properties compared analogous containing archetypal...
DPP-DTT adopts a donor-on-acceptor stacking arrangement which is preserved in thin films.