389-58-2Relevant articles and documents
One-pot cross-coupling of diborylmethane for the synthesis of dithienylmethane derivatives
Endo, Kohei,Ishioka, Takafumi,Shibata, Takanori
, p. 2184 - 2188 (2014)
The one-pot palladium-catalyzed Suzuki-Miyaura cross-coupling reaction of a diborylmethane with bromothiophene derivatives realized the synthesis of various dithienylmethane derivatives. Cyclopentadithiophenes, which are promising compounds in material science, can be obtained in good yields. The in situ generation of an unstable thienylmethylboronate is a key step for the present reaction. Georg Thieme Verlag Stuttgart New York.
Searching for Models Exhibiting High Circularly Polarized Luminescence: Electroactive Inherently Chiral Oligothiophenes
Benincori, Tiziana,Appoloni, Giulio,Mussini, Patricia Romana,Arnaboldi, Serena,Cirilli, Roberto,Quartapelle Procopio, Elsa,Panigati, Monica,Abbate, Sergio,Mazzeo, Giuseppe,Longhi, Giovanna
, p. 11082 - 11093 (2018/08/01)
Two new inherently chiral oligothiophenes characterized by the atropisomeric 3,3′-bithianaphtene scaffold functionalized with fused ring bithiophene derivatives, namely 4H-cyclopenta[2,1-b3:4b′]dithiophene (CPDT) and dithieno[3,3-b:2′,3′-d]pyrrole (DTP), were synthesized. The racemates were fully characterized and resolved into antipodes by enantioselective HPLC. The enantiomers were analyzed through different chiroptical techniques: electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) were employed to attribute the absolute configuration (AC). Comparison of experimental and calculated VCD spectra confirmed the DFT calculated conformational characteristics. The compound functionalized with two CPDT units was oxidized with FeCl3, and ECD and CPL of the resulting material were measured. Circularly polarized luminescence (CPL) was measured to verify if inherently chiral oligothiophenes could be promising systems for chiral photonics applications.
COMPOUND AND ORGANIC LIGHT EMITTING DEVICE COMPRISING THE SAME
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Page/Page column 0139; 0140; 0147; 0148; 0155; 0156, (2018/09/25)
The present specification relates to a compound and an organic light emitting device comprising the same. The compound is represented by chemical formula 1. The abovementioned compound can be used as a material for an organic material layer of an organic light emitting device. The compound according to at least one embodiment of the present invention can improve the efficiency, the low driving voltage and/or the lifetime characteristics in the organic light emitting device.COPYRIGHT KIPO 2018
Molecular engineering of face-on oriented dopant-free hole transporting material for perovskite solar cells with 19% PCE
Rakstys, Kasparas,Paek, Sanghyun,Gao, Peng,Gratia, Paul,Marszalek, Tomasz,Grancini, Giulia,Cho, Kyung Taek,Genevicius, Kristijonas,Jankauskas, Vygintas,Pisula, Wojciech,Nazeeruddin, Mohammad Khaja
supporting information, p. 7811 - 7815 (2017/07/13)
Through judicious molecular engineering, novel dopant-free star-shaped D-π-A type hole transporting materials coded KR355, KR321, and KR353 were systematically designed, synthesized and characterized. KR321 has been revealed to form a particular face-on organization on perovskite films favoring vertical charge carrier transport and for the first time, we show that this particular molecular stacking feature resulted in a power conversion efficiency over 19% in combination with mixed-perovskite (FAPbI3)0.85(MAPbBr3)0.15. The obtained 19% efficiency using a pristine hole transporting layer without any chemical additives or doping is the highest, establishing that the molecular engineering of a planar donor core, π-spacer and periphery acceptor leads to high mobility, and the design provides useful insight into the synthesis of next-generation HTMs for perovskite solar cells and optoelectronic applications.
Ligand Engineering for the Efficient Dye-Sensitized Solar Cells with Ruthenium Sensitizers and Cobalt Electrolytes
Aghazada, Sadig,Gao, Peng,Yella, Aswani,Marotta, Gabriele,Moehl, Thomas,Teuscher, Jo?l,Moser, Jacques-E.,De Angelis, Filippo,Gr?tzel, Michael,Nazeeruddin, Mohammad Khaja
supporting information, p. 6653 - 6659 (2016/07/19)
Over the past 20 years, ruthenium(II)-based dyes have played a pivotal role in turning dye-sensitized solar cells (DSCs) into a mature technology for the third generation of photovoltaics. However, the classic I3-/I- redox couple limits the performance and application of this technique. Simply replacing the iodine-based redox couple by new types like cobalt(3+/2+) complexes was not successful because of the poor compatibility between the ruthenium(II) sensitizer and the cobalt redox species. To address this problem and achieve higher power conversion efficiencies (PCEs), we introduce here six new cyclometalated ruthenium(II)-based dyes developed through ligand engineering. We tested DSCs employing these ruthenium(II) complexes and achieved PCEs of up to 9.4% using cobalt(3+/2+)-based electrolytes, which is the record efficiency to date featuring a ruthenium-based dye. In view of the complicated liquid DSC system, the disagreement found between different characterizations enlightens us about the importance of the sensitizer loading on TiO2, which is a subtle but equally important factor in the electronic properties of the sensitizers.
A versatile synthesis of long-wavelength-excitable BODIPY dyes from readily modifiable cyclopenta[2,1- B:3,4- B′ ]dithiophenes
Sutter, Alexandra,Ziessel, Raymond
, p. 1466 - 1472 (2014/06/23)
Knoevenagel condensation of a simple methylated borondipyrromethene (Bodipy) with 4,4′-dihexyl-4H-cyclopenta-[2,1-b:3,4-b′]dithiophenes functionalized at one end by a triphenylamine residue and at the other by a carbaldehyde fragment leads to novel dye species. These bisvinylic derivatives exhibit pronounced absorption in the visible range extending above 850 nm. Addition of other Bodipy units by coupling to a central iodophenyl entity enables filling of the gaps in absorption of the pivotal starting material. Efficient cascade energy transfer between the Bodipys is facilitated by spectral overlap between the energy donor and the energy acceptor. All photons between 350 nm and 750 nm are channeled to the distyryl centers which emit at 864 nm. Georg Thieme Verlag Stuttgart. New York.
Atomistic band gap engineering in donor-acceptor polymers
Gibson, Gregory L.,McCormick, Theresa M.,Seferos, Dwight S.
, p. 539 - 547 (2012/03/07)
We have synthesized a series of cyclopentadithiophene- benzochalcogenodiazole donor-acceptor (D-A) copolymers, wherein a single atom in the benzochalcogenodiazole unit is varied from sulfur to selenium to tellurium, which allows us to explicitly study sulfur to selenium to tellurium substitution in D-A copolymers for the first time. The synthesis of S- and Se-containing polymers is straightforward; however, Te-containing polymers must be prepared by postpolymerization single atom substitution. All of the polymers have the representative dual-band optical absorption profile, consisting of both a low- and high-energy optical transition. Optical spectroscopy reveals that heavy atom substitution leads to a red-shift in the low-energy transition, while the high-energy band remains relatively constant in energy. The red-shift in the low-energy transition leads to optical band gap values of 1.59, 1.46, and 1.06 eV for the S-, Se-, and Te-containing polymers, respectively. Additionally, the strength of the low-energy band decreases, while the high-energy band remains constant. These trends cannot be explained by the present D and A theory where optical properties are governed exclusively by the strength of D and A units. A series of optical spectroscopy experiments, solvatochromism studies, density functional theory (DFT) calculations, and time-dependent DFT calculations are used to understand these trends. The red-shift in low-energy absorption is likely due to both a decrease in ionization potential and an increase in bond length and decrease in acceptor aromaticity. The loss of intensity of the low-energy band is likely the result of a loss of electronegativity and the acceptor unit's ability to separate charge. Overall, in addition to the established theory that difference in electron density of the D and A units controls the band gap, single atom substitution at key positions can be used to control the band gap of D-A copolymers.
Influence of different copolymer sequences in low band gap polymers on their performance in organic solar cells
Lange, Alexander,Krueger, Hartmut,Ecker, Bernhard,Tunc, Ali Veysel,Von Hauff, Elizabeth,Morana, Mauro
experimental part, p. 1622 - 1635 (2012/06/01)
The chemical design of a polymer can be tailored by a random or a block sequence of the comonomers in order to influence the properties of the final material. In this work, two sequences, PCPDTBT and F8BT (F8), were polymerized to form a block or a random copolymer. Differences between the various polymers were examined by exploring the surface topography and charge carrier mobility. A distinct surface texture and a higher charge carrier mobility was found for the block copolymer with respect to the other materials. Solar cells were prepared with polymer:PC71BM blend active layers and the best performance of up to 2% was found for the block copolymer, which was a direct result of the fill factor. Overall, the sequences of different copolymers for solar cell applications were varied and a positive impact on efficiency was found when the block copolymer structure was utilized.
Fluorescent cyclopentadithiophene derivatives having phenyl-substituted silyl moieties
Hanamura, Hitoshi,Haneishi, Ryoko,Nemoto, Nobukatsu
, p. 4039 - 4041 (2011/08/09)
4,4-Dimethylcyclopenta[2,1-b:3,4-b′]dithiophene derivatives bearing trimethyl-, dimethylphenyl-, diphenylmethyl-, or triphenyl-silyl moieties were synthesized. The introduction of the silyl moieties onto cyclopenta[2,1-b:3,4- b′]dithiophene induced fluorescent emission as well as the bathochromic shift of wavelength at the maximum absorption and fluorescence. It was found that the larger number of phenyl group on silyl moiety resulted in the higher fluorescence quantum yield.
Synthesis and characterization of bridged bithiophene-based conjugated polymers for photovoltaic applications: Acceptor strength and ternary blends
Chen, Chiu-Hsiang,Hsieh, Chao-Hsiang,Dubosc, Martin,Cheng, Yen-Ju,Hsu, Chain-Shu
, p. 697 - 708 (2011/10/08)
Six of three-component donor-acceptor random copolymers P1-P6, symbolized as (thiophene donor)m -(thiophene acceptor)n, were rationally designed and successfully synthesized by the palladium-catalyzed Stille coupling. The 4H-cyclopenta[2,l-b:3,4-b']dithiophene (CPDT) unit serves as the donor for Pl-P4, while the benzothiadiazole (BT), quinoxaline (QU), dithienoquinoxaline, and thienopyrazine (TP) units are used as the acceptor for P1, P2, P3, and P4, respectively. P5 and P6 are structurally analogous to P1 and P2 except for using the dithieno[3,2-b:2',3'-d]silole (DTS) unit as the donor. Because the band gap lowering ability of the acceptor units in the polymer is in the order TP > BT > QU presumably due to the quinoid form population in the polymers, the optical band gaps can be well adjusted to be 1.2,1.6, and 1.8 eV for P4, P1, and P2, respectively. It is found that the two bridged bithiophene units, CPDT and DTS, have similar steric and electronic effects on the P1 and P5 as well as P2 and P6, respectively, leading to comparable intrinsic properties and device performances. Bulk heterojunction photovoltaic cells based on ITO/PEDOT:PSS/polymer:PC7BM/Ca/Al configuration were fabricated and characterized. Although P4 exhibits the lowest optical band gap, broadest absorption spectrum, and highest mobility, the too low-lying LUMO level hinders the efficient exciton dissociation, resulting in a low PCE of 0.7%. Compared with poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b'] dithiophene)-alt-4,7-(2,l,3-benzothiadiazole)] (PCPDTBT), random copolymer P1 shows more blue-shifted, broader absorption spectrum, comparable mobility, and a higher PCE of 2.0%. In view of the fact that P1 shows a higher band gap with strong absorption in visible region, while PCPDTBT has a lower band gap to mainly absorb NIR light, a BHJ device with the active layer containing ternary blend of PCPDTBT/P1/PC71BM was investigated and achieved an enhanced PCE of 2.5%, which outperforms the devices based on the binary blending systems of PCPDTBT/ PC71BM(PCE = 1.4%)orP1/PC71BM(PCE = 2.0%) under the identical conditions. Such an improvement is ascribed to the complementary absorption and compatible structure of P1 and PCPDTBT polymers.