4891-44-5Relevant articles and documents
13.4 % Efficiency from All-Small-Molecule Organic Solar Cells Based on a Crystalline Donor with Chlorine and Trialkylsilyl Substitutions
Su, Wenyan,Wang, Yang,Yin, Zhihong,Fan, Qunping,Guo, Xia,Yu, Liyang,Li, Yuxiang,Hou, Lintao,Zhang, Maojie,Peng, Qiang,Li, Yongfang,Wang, Ergang
, p. 3535 - 3543 (2021/06/25)
How to simultaneously achieve both high open-circuit voltage (Voc) and high short-circuit current density (Jsc) is a big challenge for realising high power conversion efficiency (PCE) in all-small-molecule organic solar cells (all-SM OSCs). Herein, a novel small molecule (SM)-donor, namely FYSM?SiCl, with trialkylsilyl and chlorine substitutions was designed and synthesized. Compared to the original SM-donor FYSM?H, FYSM?Si with trialkylsilyl substitution showed a decreased crystallinity and lower highest occupied molecular orbital (HOMO) level, while FYSM?SiCl had an improved crystallinity, more ordered packing arrangement, significantly lower HOMO level, and predominant “face-on” orientation. Matched with a SM-acceptor Y6, the FYSM?SiCl-based all-SM OSCs exhibited both high Voc of 0.85 V and high Jsc of 23.7 mA cm?2, which is rare for all-SM OSCs and could be attributed to the low HOMO level of FYSM?SiCl donor and the delicate balance between high crystallinity and suitable blend morphology. As a result, FYSM?SiCl achieved a high PCE of 13.4 % in all-SM OSCs, which was much higher than those of the FYSM?H- (10.9 %) and FYSM?Si-based devices (12.2 %). This work demonstrated a promising method for the design of efficient SM-donors by a side-chain engineering strategy via the introduction of trialkylsilyl and chlorine substitutions.
Compound based on benzo [1, 2-b: 4, 5-b '] dithiophene and preparation method thereof
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Paragraph 0038; 0042-0044, (2020/09/12)
The present invention provides a compound based on benzo [1, 2-b: 4, 5-b '] dithiophene, the compound has a structure represented by a formula (I), R1 is-CH, R2 is-CH, and n is aneven number selected from 1-20. The invention also provides a preparation method of the compound based on benzo [1, 2-b: 4, 5-b '] dithiophene. In a compound system provided by the invention, pi electrons have a larger delocalization range, so that pi-pi stacking between molecules can be better realized, charge transmission is facilitated, and the open-circuit voltage and the photoelectric conversion efficiency oforganic small-molecule solar cells based on the compound can be effectively improved. And the preparation method is simple, efficient and high in yield.
BODIPY based A-D-A molecules: Effect of CF3 group substitution at meso phenyl group
Johnson, Justin C.,Larson, Bryon W.,Ramamurthy, Praveen C.,Tarafdar, Gourav
, (2020/03/06)
Two pairs of A-D-A molecules have been synthesized with fluorene and benzodithiophene as the central donor subunits and terminal BODIPY units, functionalized with either a 4-methylphenyl or 4-trifluoromethylphenyl group at the meso position. The effect of the para substituent of the meso phenyl group on the photophysical properties of these molecules is studied through steady state absorption and fluorescence spectroscopy as well as femtosecond transient absorption and time resolved fluorescence spectroscopy techniques. Applicability of these molecules as donors in solution processed solar cell active layers was investigated through time resolved microwave conductivity measurements on blends with PC60BM acceptor, which shows a varying yield of charge transfer with choice of substituent. Transient absorption spectroscopy is then employed to investigate the role of the 4-trifluoromethylphenyl group in altering the efficiency of charge transfer from these A-D-A molecules to PC60BM. The results show a consistent picture of picosecond charge transfer and a component of a few hundred ps geminate recombination that results in a small yield of long-lived free charges optimized for the methylphenyl derivatives.
New dithienosilole- A nd dithienogermole-based BODIPY for solar cell applications
Thumuganti, Gayathri,Gupta, Vinay,Singh, Surya Prakash
, p. 8735 - 8740 (2019/06/14)
We report two efficient donor materials for organic solar cells, namely Si-BDP and Ge-BDP, composed by the novel union of thienyl Bodipy wings and a dithienosilole/dithienogermole core. These new donor molecules exhibited excellent solubility in organic solvents, extended π-conjugation and low-lying energy levels that matched with fullerene acceptors, supporting their application as donors in OSCs. Under optimized conditions and using PC70BM as an acceptor, desirable PCEs of 4.58% and 4.12% were observed for Si-BDP and Ge-BDP, respectively.
A new 2D-naphtho[1,2-b:5,6-b']dithiophene based donor small molecules for bulk-heterojunction organic solar cells
Bagde, Sushil S.,Park, Hanok,Tran, Van-Huong,Lee, Soo-Hyoung
, p. 30 - 39 (2018/11/30)
We present design and synthesis of three new symmetrical and linear A-D-A type π-conjugated donor small molecules (2D-NDT(TPD)2, 2D-NDT(Ester)2 and 2D-NDT(Amide)2) containing two dimensional (2D) naphthodithiophene (NDT) unit as the central donor core, end-capped with electron deficient unit such as thieno[3,4c]pyrrole-4,6-dione (TPD), 2-ethylhexyl 2-cyanoacetate (Ester) and 2-cyano-N-(2-ethylhexyl)acetamide (Amide) group respectively. We characterized these small molecules and further investigated the optical, electrochemical, morphological and photovoltaic properties. When solution–processed bulk heterojunction organic solar cells are fabricated using these small molecules, the morphology of 2D-NDT(Ester)2 or 2D-NDT(Amide)2 and [6,6]-PhenylC71-butyric acid methyl ester (PC71BM) blend film was optimized using 1,8 Diiodooctane (DIO) additive. DIO additive promotes the formation of nanoscopically well-connected molecular domains in the active blend film. A device based on (1% DIO, 1:1) 2D-NDT(Ester)2:PC71BM exhibited highest the efficiency of 1.22% with a short-circuit density (Jsc) of 3.75 mA/cm2, an open circuit voltage (Voc) of 0.91 V and fill factor (FF) of 35.50. Similarly for (1% DIO, 1:3) 2D-NDT(Amide)2:PC71BM device efficiency of 0.55%, with Jsc of 2.36 mA/cm2, Voc of 0.64 V and FF of 36.95 was observed. Whereas for (1:2) 2D-NDT(TPD)2:PC71BM device, due to the improper blending and phase separation between donor and acceptor efficiency restricted to 0.33% with Jsc of 1.66 mA/cm2, Voc of 0.73 V and FF of 27.2.
Thiadiazoloquinoxaline and benzodithiophene bearing polymers for electrochromic and organic photovoltaic applications
Hacioglu, Serife O.,Ataoglu, Emre,Hizalan, Gonul,Depci, Tolga,Cirpan, Ali,Toppare, Levent
, p. 937 - 946 (2019/03/11)
Two novel thiadiazoloquinoxaline and benzodithiophene (BDT) bearing copolymers were designed and synthesized. Different BDT units (alkoxy and thiophene substituted) were used as donor materials and the effect of alkoxy and thiophene substitution on the electrochemical, spectroelectrochemical and photovoltaic properties were investigated. Both polymers exhibited low oxidation potentials at around 0.90 V and low optical band gaps at around 1.00 eV due to the insertion of electron poor thiadiazoloquinoxaline unit into the polymer backbone. Both P1 (poly-6,7-bis(3,4-bis(decyloxy)phenyl)-4-(4,8-bis(nonan-3-yloxy)benzo[1,2-b:4,5-b']dithiophen-2-yl)-[1, 2, 5]thiadiazolo[3,4-g]quinoxaline) and P2 (poly- 4-(4,8-bis(5-(nonan-3-yl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophen-2-yl)-6,7-bis(3,4-bis(decyloxy)phenyl)-[1, 2, 5]thiadiazolo[3,4-g]quinoxaline) exhibited multichromic behavior with different tones of greenish yellow and gray in the neutral and fully oxidized states, respectively. In addition, both polymers revealed very high optical contrasts (～87%) in the NIR region which make these promising polymers good candidates for NIR applications. Finally, in order to explore the organic photovoltaic performances, P1 and P2 were mixed with PC71BM in the active layer of organic solar cells (OSCs) by conventional device structure. As a result P1 and P2 based devices revealed power conversion efficiencies (PCEs) of 0.33% and 0.60% respectively. However, the additive treatment enhanced PCE from 0.49 to 0.73% for P2 based devices.
Preparation method of 2-bromo-5-(2-ethylhexyl) thiophene
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Paragraph 0048; 0053-0054; 0060-0061; 0067-0068, (2018/05/01)
The invention provides a preparation method of 2-bromo-5-(2-ethylhexyl) thiophene. The preparation method comprises the following steps: 1) mixing thiophene, 2-ethylhexyl acyl chloride and aluminum chloride anhydrous in anhydrous dichloromethane, stirring the mixture at room temperature to react, and then carrying out quenching and post-treatment to obtain 2-(2-ethylhexyl) thiophene; 2) mixing theprepared 2-(2-ethylhexyl) thiophene, hydrazine hydrate, triethylene glycol and sodium hydroxide, heating and stirring the mixture to reflux, after reaction, changing a reflux device into a distillingdevice, adding water, carrying out distillation by water steam, and separating the liquid to obtain 2-(2-ethylhexyl) thiophene; and 3) mixing the prepared 2-(2-ethylhexyl) thiophene, hydrobromic acidand hydrogen peroxide, stirring the mixture at room temperature to react, and separating the liquid to obtain the 2-bromo-5-(2-ethylhexyl) thiophene. The preparation method provided by the inventionis mild in condition, high in yield, relatively easy in post-treatment and suitable for scaled preparation, avoids use of low temperature and dangerous reagents, and is safe and simple to operate.
Star-shaped and linear TT-conjugated oligomers consisting of a tetrathienoanthracene core and multiple diketopyrrolopyrrole arms for organic solar cells
Komiyama, Hideaki,Adachi, Chihaya,Yasuda, Takuma
supporting information, p. 1459 - 1466 (2016/08/02)
Solution-processable star-shaped and linear π-conjugated oligomers consisting of an electron-donating tetrathienoanthracene (TTA) core and electron-accepting diketopyrrolopyrrole (DPP) arms, namely, TTA-DPP4 and TTA-DPP2, were designed and synthesized. Ba
Solution-processable thiadiazoloquinoxaline-based donor-acceptor small molecules for thin-film transistors
Gu, Pei-Yang,Zhang, Jing,Long, Guankui,Wang, Zilong,Zhang, Qichun
supporting information, p. 3809 - 3814 (2016/05/19)
Although several [1,2,5]thiadiazolo[3,4-g]quinoxaline (TQ)-thiophene-based hybrid polymers have been demonstrated for application in organic field-effect transistors (OFETs), the research on the charge carrier mobility of conjugated donor (D)-acceptor (A) small molecules is rare. To enrich the TQ-containing small molecule family, in this paper, we designed and synthesized three novel TQ derivatives 1, 2, and 3 with thiophene units attached onto the TQ cores. The optoelectronic and OFET properties of as-prepared compounds 1-3 are investigated. Our results indicate that compounds 1-3 show typical p-type characteristics with mobility as high as 0.012, 0.05 and 0.0055 cm2 V-1 s-1 and on/off current ratios of 3 × 105, 1 × 106 and 1 × 104 under the optimized conditions, respectively. Due to the steric effect of the substituted bulky group, compound 3 adopts a looser packing mode with a larger π-π distance, which subsequently reduces the transport performance. Our results suggest that the D-A π-conjugated small molecules based on TQ could be good candidates for application in organic electronic devices.
Cobalt-Catalyzed Reductive Alkylation of Heteroaryl Bromides: One-Pot Access to Alkylthiophenes, -furans, -selenophenes, and -pyrroles
Cai, Deng-Jhou,Lin, Po-Han,Liu, Ching-Yuan
supporting information, p. 5448 - 5452 (2015/08/24)
A practical and convenient Co-catalyzed alkylation method for the facile introduction of various alkyl chains into organic electronically significant heteroaryl compounds, including thiophenes, furans, selenophenes, and pyrroles, is reported. Under well-optimized reaction conditions, a wide range of alkylated heteroaryl compounds have beeen efficiently prepared in moderate to good isolated yields. Notably, 2- or 3-alkylthiophenes, which play a decisive role in polymer chemistry and organic materials, have been synthesized step-economically for the first time by this reductive-coupling methodology using inexpensive cobalt salts as catalysts. This straightforward synthetic procedure avoids the preparation of moisture-unstable organometallic reagents (RMgX or RZnX) required in conventional alkylation protocols. Various alkyl chains have been introduced into organic, electronically important heteroaryl compounds step-economically through Co-catalyzed reductive alkylation reactions. The resulting alkylheteroarenes are indispensable building blocks for polymer chemistry and π-functional organic materials.
