A5045497271- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Organic Light-Emitting Diodes Research
- Perovskite Materials and Applications
- Semiconductor materials and interfaces
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Photochemistry and Electron Transfer Studies
- Thin-Film Transistor Technologies
- Organoboron and organosilicon chemistry
- Transition Metal Oxide Nanomaterials
- Fullerene Chemistry and Applications
- Catalytic Cross-Coupling Reactions
- Crystallography and molecular interactions
- Synthetic Organic Chemistry Methods
- Molecular Junctions and Nanostructures
- Porphyrin and Phthalocyanine Chemistry
- Carbon Nanotubes in Composites
- Polydiacetylene-based materials and applications
- solar cell performance optimization
- Nanowire Synthesis and Applications
- Advanced Sensor and Energy Harvesting Materials
- Synthesis and properties of polymers
- Covalent Organic Framework Applications
- Photochromic and Fluorescence Chemistry
Université Laval
2011-2024
Direction de la Recherche Technologique
2017
McGill University
2017
Institute for Microstructural Sciences
2010
University of California, Santa Barbara
2010
Defence Research and Development Canada
2006-2009
Université de Montréal
2000-2001
A new alternating copolymer of dithienosilole and thienopyrrole-4,6-dione (PDTSTPD) possesses both a low optical bandgap (1.73 eV) deep highest occupied molecular orbital energy level (5.57 eV). The introduction branched alkyl chains to the unit was found be critical for improvement polymer solubility. When blended with PC71BM, PDTSTPD exhibited power conversion efficiency 7.3% on photovoltaic devices an active area 1 cm2.
A new low-band-gap thieno[3,4-c]pyrrole-4,6-dione-based copolymer, PBDTTPD, has been designed and synthesized. PBDTTPD is soluble in chloroform or o-dichlorobenzene upon heating shows a broad absorption the visible region. The HOMO LUMO energy levels were estimated to be at −5.56 −3.75 eV, respectively. These electrochemical measurements fit well with an optical bandgap of 1.8 eV. When blended PC71BM, this polymer demonstrated power conversion efficiency 5.5% bulk-heterojunction photovoltaic...
Organic bulk-heterojunction solar cells comprising poly[N-9'-hepta-decanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2', 1',3'-benzothiadiazole) (PCDTBT) are systematically aged and demonstrate lifetimes approaching seven years, which is the longest reported lifetime for polymer cells. An experimental set-up described that capable of testing large numbers cells, holding each device at its maximum power point while controlling monitoring temperature light intensity. Detailed facts importance...
Narrow bandgap n-type organic semiconductors (n-OS) have attracted great attention in recent years as acceptors solar cells (OSCs), due to their easily tuned absorption and electronic energy levels comparison with fullerene acceptors. Herein, a new n-OS acceptor, Y5, an electron-deficient-core-based fused structure is designed synthesized, which exhibits strong the 600-900 nm region extinction coefficient of 1.24 × 105 cm-1 , electron mobility 2.11 10-4 cm2 V-1 s-1 . By blending Y5 three...
Abstract A series of low‐bandgap alternating copolymers dithienosilole and thienopyrrolodione (PDTSTPDs) are prepared to investigate the effects polymer molecular weight alkyl chain length thienopyrrole‐4,6‐dione (TPD) unit on photovoltaic performance. High‐molecular‐weight PDTSTPD leads a higher hole mobility, lower device resistance, larger fill factor, photocurrent in PDTSTPD:[6,6]‐phenyl C 71 butyric acid methyl ester (PC BM) bulk‐heterojunction solar cells. Different side‐chain lengths...
We report the synthesis of novel fluorene-based π-conjugated polymers and investigation their electroluminescent properties in organic light-emitting devices. also on photo- electroluminescence materials same class whose was recently published. The alternated incorporation phenylene or thiophene moieties leads to tunability properties. spectral emission varies from blue green yellow, depending composition copolymers. To enhance luminous efficiency devices, hole injection transport into...
We have studied the utilization of PCDTBT, an alternating poly(2,7-carbazole) derivative, in organic bulk heterojunction solar cells. The effect polymer molecular weight, PCDTBT:[60]PCBM ratio, and active layer thickness on device performance is reported. best was obtained when number-average weights (Mn) are around 20 kDa with a polydispersity index 2.2. Both ratio affect light absorption charge transport properties. By optimizing these two parameters, power conversion efficiency (PCE) up...
Since its inception in 1995, significant advances the field of bulk heterojunction (BHJ) solar cells have been made and polymeric semiconductors are now considered to be one most promising ways lower cost energy generated by cells. Power conversion efficiencies (PCEs) reaching threshold values for commercialisation (9.2% single-layer BHJ 10.6% tandem devices). PCDTBT, a carbazole-based copolymer, is among efficient, stable low-cost materials with high open-circuit voltage (Voc ∼ 0.90 V),...
This Review covers recent progress made in the synthesis of carbazole-based monomers and polymers their applications plastic electronics. That includes first photoactive carbazole-containing polymer, namely PVK, conjugated poly(3,6-carbazole)s, finally latest developments poly(2,7-carbazole) derivatives. We will mainly discuss photovoltaic cell because impressive performances that have been obtained past couple years. Semi-ladder poly(indolo[3,2-b]carbazole)s recently shown interesting...
Abstract A new class of low‐bandgap copolymers based on benzodithiophene (BDT) and thieno[3,4‐c]pyrrole‐4,6‐dione (TPD) units is reported. Chemical modifications the conjugated backbone promote both high molecular weights processability while allowing for tuning electronic properties. Copolymers with substituted thiophene spacers (alkyl chains facing BDT unit) or unsubstituted tend to have low power conversion efficiencies (PCE less than 1%) due a bad morphology active layer, whereas TPD...
We report the synthesis and characterization of three new poly(2,7-carbazole) derivatives, namely, poly[N-9-heptadecanyl-2,7-carbazole-alt-5,7-di(3-octylthien-2-yl)-2,3-di(thien-3-yl)-thieno[3,4-b]pyrazine (P1), poly[N-9-heptadecanyl-2,7-carbazole-alt-5,7-di(3-octylthien-2-yl)-2,3-di(phen-1-yl)-thieno[3,4-b]pyrazine (P2), poly[N-9-heptadecanyl-2,7-carbazole-alt-5,7-di(3-octylthien-2-yl)-2,3-di(4-octylphen-1-yl)-thieno[3,4-b]pyrazine (P3), which reflect green light in their neutral state show...
The thermal stability of the poly(2,7-carbazole) derivative (PCDTBT) is investigated. UV–visible absorption spectra and X-ray photoelectron spectroscopy data demonstrate that electronic structure PCDTBT stable in air at annealing temperatures up to 150 °C N2 even after exposure 350 °C. Field-effect transistors fabricated with show characteristics hole mobility (air) (N2). Detailed facts importance specialist readers are published as "Supporting Information". Such documents peer-reviewed, but...
The ongoing depletion of fossil fuels has led to an intensive search for additional renewable energy sources. Solar-based technologies could provide sufficient satisfy the global economic demands in near future. Photovoltaic (PV) cells are most promising man-made devices direct solar utilization. Understanding charge separation and transport PV materials at a molecular level is crucial improving efficiency cells. Here, we use light-induced EPR spectroscopy combined with DFT calculations...
Intrinsic traps in organic semiconductors can be eliminated by trap-filling with F4-TCNQ. Photovoltaic tests show that devices F4-TCNQ at parts per thousand concentration outperform control due to an improved fill factor. Further studies confirm the pathway and demonstrate general nature of this finding. As a service our authors readers, journal provides supporting information supplied authors. Such materials are peer reviewed may re-organized for online delivery, but not copy-edited or...
The ground and excited states of covalently linked fluorene-based dimers were investigated by theoretical methods UV−vis fluorescence spectroscopies. optimized structures the characterization frontier molecular orbitals obtained HF/6-31G* ab initio calculations. All derivatives are nonplanar in their electronic states. extent nonplanarity depends on nature aromatic ring bonded to fluorene unit. involved both subunits dyads. HOMO each compound possesses an antibonding character between...
We report the preparation and characterization of new electrochromic polymers containing a 4-butyltriphenylamine (BuTPA) unit on main chain. All were obtained through Suzuki−Miyaura cross-coupling reaction between 4-butyl-N,N-bis((4,4,5,5-tetramethyl-1,3,2-dioxaborolan-4-phenyl)aniline) several aryl dibromide molecules to modulate electronic properties resulting copolymers. 2,5-Dibromothiophene, 2,5-dibromo(3,4-ethylenedioxythiophene), 3,6-dibromo-N-octylcarbazole,...
The syntheses of new fluorene-based π-conjugated copolymers; namely, poly((5,5″-(3′,4′-dihexyl-2,2′;5′,2″-terthiophene 1′,1′-dioxide))-alt-2,7-(9,9-dihexylfluorene)) (PFTORT), poly((5,5″″-(3″,4″-dihexyl-2,2′:5′,2′:5″,2‴:5‴,2″″-quinquethiophene 1″,1″-dioxide))-alt-2,7-(9,9-dihexylfluorene)) (PFTTORTT), and poly((5,5-E-α-(2-thienyl)methylene)-2-thiopheneacetonitrile)-alt-2,7-(9,9-dihexylfluorene)) (PFTCNVT), are reported. In the solid state, PFTORT PFTCNVT present red–orange emission (with a...
Charge carrier photogeneration and decay were studied in poly[N-${9}^{\ensuremath{''}}$-hepta-decanyl- 2,7-carbazole-alt-5,5-(${4}^{\ensuremath{'}},{7}^{\ensuremath{'}}$-di-2-thienyl-${2}^{\ensuremath{'}},{1}^{\ensuremath{'}},{3}^{\ensuremath{'}}$-benzothiadiazole)], PCDTBT, phase-separated mixtures of PCDTBT with the fullerene derivative [6,6]-phenyl ${\text{C}}_{70}$-butyric acid methyl ester $({\text{PC}}_{70}\text{BM})$. The absorption spectrum exhibits two distinct bands centered at...
We combined experimental and computational approaches to tune the thickness of films in poly(N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole) (PCDTBT)-based organic solar cells maximize absorption by active layer. High power-conversion efficiencies 5.2% 5.7% were obtained on PCDTBT-based when using [6,6]-phenyl C61-butyric acid methyl ester (PC60BM) C71-butyric (PC70BM) as electron acceptor, respectively. The are designed have an area 1.0 cm2, which is...