69620-20-8Relevant articles and documents
Photon upconverting liquids: Matrix-free molecular upconversion systems functioning in air
Duan, Pengfei,Yanai, Nobuhiro,Kimizuka, Nobuo
, p. 19056 - 19059 (2013)
A nonvolatile, in-air functioning liquid photon upconverting system is developed. A rationally designed triplet sensitizer (branched alkyl chain-modified Pt(II) porphyrin) is homogeneously doped in energy-harvesting liquid acceptors with a 9,10-diphenylanthracene unit. A significantly high upconversion quantum yield of ～28% is achieved in the solvent-free liquid state, even under aerated conditions. The liquid upconversion system shows a sequence of efficient triplet energy transfer and migration of two itinerant excited states which eventually collide with each other to produce a singlet excited state of the acceptor. The observed insusceptibility of upconversion luminescence to oxygen indicates the sealing ability of molten alkyl chains introduced to liquefy chromophores. The involvement of the energy migration process in triplet-triplet annihilation (TTA) provides a new perspective in designing advanced photon upconversion systems.
Synthesis and electronic energy-level regulation of imide-fused poly(thienylene vinylene) derivatives
Wang, Xiaochen,Gao, Chen,Wang, Kai,Fan, Xi,Wang, Haiqiao,Li, Xiaoyu,Zhang, Zhi-Guo,Li, Yongfang
, p. 4975 - 4982 (2013)
A series of novel poly(thienylene vinylene) derivatives (PTVs), P20-P24, with imide substituents were designed and synthesized by palladium-catalyzed Stille coupling polymerization, wherein the imide substituent density was decreased gradually, which allowed us to explicitly study the effect of electron-deficient substituent on the optical, electrochemical, and photovoltaic properties of the PTVs. All of the four polymers showed broad absorption bands with optical bandgaps between1.66 and 1.78 eV. By reducing density of electron-deficient imide group, the LUMO energy levels of the polymers could be tuned gradually from -3.75 to -3.43 eV, with HOMO levels upshifted from -5.64 to -5.16 eV. Bulk heterojunction solar cells with the polymers as donor and PC71BM as acceptor demonstrated very different excitons dissociation behavior. With decreasing the imide-fused unit density, the open-circuit voltage (VOC) values in the devices decreased from 0.78 to 0.62 V, whereas the short-circuit currents (JSC) increased from 0 to 2.26 mA cm -2 and then decreased to 1.01 mA cm-2. By adjusting the electron-withdrawing imide substituent density, power conversion efficiency of the PTVs-based solar cells can be increased to four times, reached 0.86%. To the best of our knowledge, this is the first systematic study of the relationship between molecular energy level and photovoltaic properties of PTVs. Copyright
Design of fullerene-free electron-acceptor materials containing perylenediimide units for solution-processed organic electronic devices
Aoyagi, Koutarou,Shoji, Yu,Otsubo, Saika,Kawauchi, Susumu,Ueda, Mitsuru,Matsumoto, Hidetoshi,Higashihara, Tomoya
, p. 1083 - 1093 (2014)
Organic electron-accepting materials with light absorbance and wide absorption bands are sorely needed as alternatives to fullerene derivatives for organic electronics, in particular for organic photovoltaic (OPV) applications. In the present study, we ha
Aromatic donor-acceptor interactions in non-polar environments
Prentice, Giles M.,Pascu, Sofia I.,Filip, Sorin V.,West, Kevin R.,Panto?, G. Dan
, p. 8265 - 8268 (2015)
We have evaluated the strength of aromatic donor-acceptor interactions between dialkyl naphthalenediimide and dialkoxynaphthalene in non-polar environments. 1H NMR, UV-vis spectroscopy and isothermal titration calorimetry were used to characterise this interaction. We concluded that the strength of donor-acceptor interactions in heptane is sufficient to drive supramolecular assemblies in this and other aliphatic solvents.
New ladder-type conjugated polymer with broad absorption, high thermal stability, and low band gap
Wang, Shitao,Hong, Wei,Ren, Shendong,Li, Jie,Wang, Mao,Gao, Xike,Li, Hongxiang
, p. 4272 - 4276 (2012)
New ladder-type π-conjugated polymer poly{6-alkyl-pyrrolo[3,2-b:4,5-b'] bis-[1,4]benzothiazine} (PPBBTZ) was synthesized through a simple method. PPBBTZ showed good solubility in organic solvents (such as chloroform, tetrahydrofuran, chlorobenzene, o-dichlorobenzene) and high thermal stability (decomposition temperatures up to 323 °C and 299 °C in nitrogen and air, respectively). The highest occupied molecular orbital and lowest unoccupied molecular orbital energy level estimated from electrochemistry result and absorption spectrum were -5.46 and -3.81 eV, respectively, with a band gap of 1.65 eV. More interestingly, PPBBTZ displayed broad absorption from ultraviolet to visible light regions (200-750 nm). These properties suggested PPBBTZ was a good candidate in opto-electronics.
δ-Methyl Branching in the Side Chain Makes the Difference: Access to Room-Temperature Discotics
Kirres, Jochen,Knecht, Friederike,Seubert, Philipp,Baro, Angelika,Laschat, Sabine
, p. 1159 - 1165 (2016)
Although discotic liquid crystals are attractive functional materials, their use in electronic devices is often restricted by high melting and clearing points. Among the promising candidates for applications are [15]crown-5 ether-based liquid crystals with peripheral n-alkoxy side chains, which, however, still have melting points above room temperature. To overcome this problem, a series of o-terphenyl and triphenylene [15]crown-5 ether derivatives was prepared in which δ-methyl-branched alkoxy side chains of varying lengths substitute the peripheral linear alkoxy chains. The mesomorphic properties of the novel crown ethers were studied by differential scanning calorimetry, polarizing optical microscopy, and X-ray diffraction. δ-Methyl branching indeed lowers melting points resulting in room-temperature hexagonal columnar mesophases. The mesophase widths, which ranged from 87 to 30 K for o-terphenyls, significantly increased to 106-147 K for the triphenylenes depending on the chain lengths, revealing the beneficial effect of a flat mesogen, due to improved π-π interactions.
Orthogonal 4,10 and 6,12 substitution of dibenzo[def,mno]chrysene polycyclic aromatic small molecules
Koldemir, Unsal,Tinkham, Jonathan S.,Johnson, Robert,Lim, Bogyu,Yemam, Henok A.,Gagnon, Kevin J.,Parkin, Sean,Sellinger, Alan
, p. 8723 - 8733 (2017)
A series of new polycyclic aromatic hydrocarbon compounds based on (4,10-disubstituted-dibenzo[def,mno]chrysene-6,12-dione) and 4,10 di-substituted 6,12-bis(triisopropylsilylethynyl)dibenzo[def,mno]chrysene are reported with tunable electronic properties
Tuning the Mesomorphism and Redox Response of Anionic-Ligand-Based Mixed-Valent Nickel(II) Complexes by Alkyl-Substituted Quaternary Ammonium Cations
Nakamura, Yuichi,Matsumoto, Takeshi,Sakazume, Yasutaka,Murata, Junnosuke,Chang, Ho-Chol
, p. 7398 - 7409 (2018)
The combination of the redox-active mesogenic anion [NiII(Bdt)(BdtSQ)]? (Bdt=1,2-benzenedithiolato; BdtSQ=1,2-dithia-semi-benzoquinonato) with alkyl-substituted ammonium cations afforded a series of redox-active ionic complexes of the type [NR4][NiII(Bdt)(BdtSQ)] [R=nC16H33 (NC164Ni) and C8,10 (NC8,104Ni); C8,10=6-octylhexadecyl] or [NMe2R2][NiII(Bdt)(BdtSQ)] [R=nC16H33 (NMe2C162Ni) and C8,10 (NMe2C8,102Ni)]. X-ray crystallographic analyses of NMe2C162Ni and NC164Ni revealed the formation of cation-dependent integrated ionic layers separated by interdigittated alkyl chains. Complexes NMe2C162Ni and NC164Ni commonly form crystalline phases at room temperature, whereas complexes NMe2C8,102Ni and NC8,104Ni, which contain branched alkyl chains, form a metastable mesophase and an amorphous phase at the same temperature, respectively. Furthermore, complexes NMe2C162Ni, NMe2C8,102Ni, and NC164Ni commonly form a smectic A phase (SmA) at 375, 317, and 342 K, respectively. For the four complexes, well-defined cyclic voltammetry responses, derived from ligand-based oxidation and reduction, were observed in solution and the condensed phases, that is, upon casting these complexes on an indium-doped tin oxide working electrode. The present study demonstrates the tunability of the mesomorphism of ionic molecular assemblies composed of alkyl-substituted quaternary ammonium cations, while maintaining the well-defined redox responses of the anions even in the condensed phases.
Ultralow bandgap molecular semiconductors for ambient-stable and solution-processable ambipolar organic field-effect transistors and inverters
Ozdemir, Resul,Choi, Donghee,Ozdemir, Mehmet,Kwon, Guhyun,Kim, Hyekyoung,Sen, Unal,Kim, Choongik,Usta, Hakan
, p. 2368 - 2379 (2017)
The design and development of novel ambipolar semiconductors is very crucial to advance various optoelectronic technologies including organic complementary (CMOS) integrated circuits. Although numerous high-performance ambipolar polymers have been realized to date, small molecules have been unable to provide high ambipolar performance in combination with ambient-stability and solution-processibility. In this study, by implementing highly π-electron deficient, ladder-type IFDK/IFDM acceptor cores with bithiophene donor units in D-A-D π-architectures, two novel small molecules, 2OD-TTIFDK and 2OD-TTIFDM, were designed, synthesized and characterized in order to achieve ultralow band-gap (1.21-1.65 eV) semiconductors with sufficiently balanced molecular energetics for ambipolarity. The HOMO/LUMO energies of the new semiconductors are found to be ?5.47/?3.61 and ?5.49/?4.23 eV, respectively. Bottom-gate/top-contact OFETs fabricated via solution-shearing of 2OD-TTIFDM yield perfectly ambient stable ambipolar devices with reasonably balanced electron and hole mobilities of 0.13 cm2 V?1 s?1 and 0.01 cm2 V?1 s?1, respectively with Ion/Ioff ratios of ～103-104, and 2OD-TTIFDK-based OFETs exhibit ambipolarity under vacuum with highly balanced (μe/μh ～ 2) electron and hole mobilities of 0.02 cm2 V?1 s?1 and 0.01 cm2 V?1 s?1, respectively with Ion/Ioff ratios of ～105-106. Furthermore, complementary-like inverter circuits were demonstrated with the current ambipolar semiconductors resulting in high voltage gains of up to 80. Our findings clearly indicate that ambient-stability of ambipolar semiconductors is a function of molecular orbital energetics without being directly related to a bulk π-backbone structure. To the best of our knowledge, considering the processing, charge-transport and inverter characteristics, the current semiconductors stand out among the best performing ambipolar small molecules in the OFET and CMOS-like circuit literature. Our results provide an efficient approach in designing ultralow band-gap ambipolar small molecules with good solution-processibility and ambient-stability for various optoelectronic technologies, including CMOS-like integrated circuits.
Synthesis of new symmetrical carbazole- and fluorene-containing α-diketones
Keshtov,Osipov,Topchiy,Zotova,Konstantinov,Krayushkin,Kuklin,Khokhlov
, p. 215 - 220 (2015)
A simple and convenient one-step method for the preparation of symmetrical α-diketones has been proposed. The latter are intended to be used in synthesis of new carbazole- and fluorene-containing quinoxalines showing electroluminescent and photovoltaic properties.
