2,1,3-Benzothiadiazole-5,6-dicarboxylicimide-Based Polymer Semiconductors for Organic Thin-Film Transistors and Polymer Solar Cells

Yu, Jianwei,Ornelas, Joshua Loroñ,a,Tang, Yumin,Uddin, Mohammad Afsar,Guo, Han,Yu, Simiao,Wang, Yulun,Woo, Han Young,Zhang, Shiming,Xing, Guichuan,Guo, Xugang,Huang, Wei American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.48

<P>A series of polymer semiconductors incorporating 2,1,3-benzothiadiazole-5,6-dicarboxylicimide (BTZI) as strong electron-withdrawing unit and an alkoxy-functionalized head-to-head linkage containing bithiophene or bithiazole as highly electron-rich co-unit are designed and synthesized. Because of the strong intramolecular charge transfer characteristics, all three polymers BTZI-TRTOR (P1), BTZI-BTOR (P2), and BTZI-BTzOR (P3) exhibit narrow bandgaps of 1.13, 1.05, and 0.92 eV, respectively, resulting in a very broad absorption ranging from 350 to 1400 nm. The highly electron-deficient 2,1,3-benzothiadiazole-5,6-dicarboxylicimide and alkoxy-functionalized bithiophene (or thiazole) lead to polymers with low-lying lowest unoccupied molecular orbitals (-3.96 to -4.28 eV) and high-lying highest occupied molecular orbitals (-5.01 to -5.20 eV). Hence, P1 and P3 show substantial and balanced ambipolar transport with electron mobilities/hole mobilities of up to 0.86/0.51 and 0.95/0.50 cm(2) V-1 s(-1), respectively, and polymer P2 containing the strongest donor unit exhibited unipolar p-type performance with an average hole mobility of 0.40 cm(2) V-1 s(-1) in top-gate/bottom-contact thin-film transistors with gold as the source and drain electrodes. When incorporated into bulk heterojunction polymer solar cells, the narrow bandgap (1.13 eV) polymer P1 shows an encouraging power conversion efficiency of 4.15% with a relatively large open-circuit voltage of 0.69 V, which corresponds to a remarkably small energy loss of 0.44 eV. The power conversion efficiency of P1 is among the highest reported to date with such a small energy loss in polymer:fullerene solar cells.</P>

A Cut‑Out Strategy for Wind Turbines that Ensures Low‑Voltage Ride‑Through Capability

Aiguo Tan,Zhihan Tang,Xianbo Sun,Jianwei Zhong,Honghua Liao,Haibing Fang 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

To ensure the dynamic stability of the system and improve low-voltage ride-through (LVRT) capability, this study presents a cut-out strategy for doubly-fed induction generator (DFIG) wind turbines that combines reactive power output with asynchronous load reduction. This strategy reduces the risk of the large-scale disconnection of DFIGs in a wind farm by regulating the reactive power output of DFIGs in the wind farm and removing DFIGs in an asynchronous state based on the reduction ratio. Simulation results demonstrate that the implementation of this strategy can help increase the voltage at the point of common coupling and the LVRT time for a wind farm.

1,4-Di(3-alkoxy-2-thienyl)-2,5-difluorophenylene: A Building Block Enabling High-Performance Polymer Semiconductors with Increased Open-Circuit Voltages

Chen, Jianhua,Yan, Zhenglong,Tang, Linjing,Uddin, Mohammad Afsar,Yu, Jianwei,Zhou, Xin,Yang, Kun,Tang, Yumin,Shin, Tae Joo,Woo, Han Young,Guo, Xugang American Chemical Society 2018 Macromolecules Vol.51 No.14

<P>A new building block, 1,4-di(3-alkoxy-2-thienyl)-2,5-difluorophenylene (DOTFP) with several desirable features such as high backbone planarity, suitably lying highest occupied molecular orbital (HOMO), and good solubility, was developed by inserting an electron-deficient difluorophenylene into the 3,3′-dialkoxy-2,2′-bithiophene (BTOR) unit. Three regioregular D-A<SUB>1</SUB>-D-A<SUB>2</SUB> type polymers based on DOTFP and benzothiadiazole (BT) derivatives were synthesized and characterized by comparing with a D-A type BTOR-based polymer. The content of highly electron-rich alkoxythiophene is reduced by half in the DOTFP-based polymers versus that of the BTOR-based polymer analogue, which results in a deeper HOMO level and benefits high open-circuit voltage (<I>V</I><SUB>oc</SUB>) in polymer solar cells (PSCs). Consequently, the DOTFP-ffBT-based solar cells exhibited a significantly improved power conversion efficiency (PCE) of 8.7% and an increased <I>V</I><SUB>oc</SUB> of 0.84 V compared to the BTOR-ffBT-based solar cells with a PCE of 2.6% and a <I>V</I><SUB>oc</SUB> of 0.49 V. Additionally, the DOTFP-based polymers showed improved charge transport properties and film morphology than the BTOR-based polymer BTOR-ffBT, resulting in simultaneous enhancement of the short-circuit current (<I>J</I><SUB>sc</SUB>) and fill factor (FF) in PSCs. These results demonstrate the great promise of the DOTFP building block for the construction of high-performance photovoltaic polymer semiconductors with increased <I>V</I><SUB>oc</SUB>s.</P> [FIG OMISSION]</BR>

Genetic Algorithm‑Based Analysis of the Efects of an Additional Damping Controller for a Doubly Fed Induction Generator

Aiguo Tan,Zhihan Tang,Xianbo Sun,Jianwei Zhong,Honghua Liao,Haibing Fang 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.4

In view of the problem that large-scale and high-penetration wind power access may weaken the stability of small interference in the power grid, this study proposes a novel additional damping controllers for the doubly-fed induction generator (DFIG) based on the genetic algorithm. A DFIG model and its control system is built, and the parameters of the controller are tuned using the genetic algorithm to optimize the control efect. Based on Western System Coordinating Council (WSCC) 3-machine 9-node system, multi-scenario simulation results verifes that the additional damping controller proposed in this study performs better to suppress the low-frequency oscillation than the power system stabilizer (PSS) installed on the synchronous generators which are farther to the disturbance point. Meanwhile, the proposed strategy is compared with the reactive power modulation control, which can provide a reference for engineering applications of an added DFIG damping controller.

Efficient photocatalytic degradation of 2-chloro-4,6-dinitroresorcinol in salty industrial wastewater using glass-supported TiO2

Yuan Zhang,Wenwei Jiang,Yongsheng Ren,Baoming Wang,Yong Liu,Quanxian Hua,Jianwei Tang 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.3

2-chloro-4,6-dinitroresorcinol (CDNR) is detrimental to the environment and human health owing to its high toxicity and poor biodegradability. To demonstrate the feasibility of photocatalytic degradation of CDNR from industrial salty wastewater by borosilicate glass supported TiO2 under UV light irradiation, borosilicate glass supported TiO2 was prepared successfully by a novel sol-gel route via dip-coating method and characterized by XRD, SEM, FTIR and XPS analysis. The results showed that TiO2 catalyst has the anatase phase structure with crystallite size of 11.5 nm and coats uniformly on the borosilicate glass. Also, the effects of reaction time, pH value, TiO2 dosage, CDNR concentration, and Cl on the degradation efficiency of CDNR were investigated. The results indicated that at pH 2, reaction time 3.5 h, CDNR concentration 10mg/L, NaCl concentration 5.85% (w/w) and TiO2 dosage 1.0 g/L, 97.7% of CDNR was degraded in the presence of Cl, this corresponded to a rate constant of 1.05 h1, illustrating the feasibility of photocatalytic degradation process. This contribution provides a basic investigation regarding the potential application of borosilicate glass supported TiO2.

Backbone Conformation Tuning of Carboxylate-Functionalized Wide Band Gap Polymers for Efficient Non-Fullerene Organic Solar Cells

Chen, Jianhua,Wang, Lei,Yang, Jie,Yang, Kun,Uddin, Mohammad Afsar,Tang, Yumin,Zhou, Xin,Liao, Qiaogan,Yu, Jianwei,Liu, Bin,Woo, Han Young,Guo, Xugang American Chemical Society 2019 Macromolecules Vol.52 No.1

<P>Two carboxylate-functionalized wide band gap polymers, 2TC-TT-BDTFT and 2T-TTC-BDTFT, which feature a fluorinated benzodithiophene (BDTFT)-<I>alt</I>-2,5-di(thiophen-2-yl)thieno[3,2-<I>b</I>]thiophene (2T-TT) backbone having different carboxylate attaching positions, were designed and synthesized. By variation of the substitution position of carboxylate groups on the 2T-TT unit, the backbone conformation of the designed building blocks 2TC-TT and 2T-TTC and their corresponding donor-acceptor polymers was fine-tuned as demonstrated by single crystal study and DFT calculation, thus yielding a large device performance difference in organic solar cells. As a result of the relatively higher planarity of the 2T-TTC unit in which the two carboxylate groups were attached on the inner thieno[3,2-<I>b</I>]thiophene moiety, the 2T-TTC-BDTFT polymer exhibited a red-shifted UV-vis absorption, stronger aggregation, and improved charge transport property than its polymer analogue 2TC-TT-BDTFT, in which the two outer thiophene rings were functionalized with carboxylate groups. Benefiting from the improved exciton dissociation and charge collection efficiency, better film morphology, and higher photoresponse, non-fullerene organic solar cells based on 2T-TTC-BDTFT:m-ITIC achieved a power conversion efficiency (PCE) of 11.15% with a fill factor (FF) of ∼70%, while the 2TC-TT-BDTFT:m-ITIC cells showed a relatively lower PCE of 9.65% and FF of 59.31%. The much higher FF of 2T-TTC-BDTFT-based solar cells reflects the great merit of the carboxylation on thienothiophene moiety rather than the outer thiophene counterpart. Therefore, the modulation of the carboxylate position on polymer backbones is an efficient strategy to tune the backbone conformation, interchain packing, film morphology, and the resulting optical, electrical, and photovoltaic properties. Moreover, both the 2T-TTC-BDTFT:m-ITIC and 2TC-TT-BDTFT:m-ITIC solar cells showed excellent stability during annealing and long-term storage. These results demonstrate that carboxylate-functionalized 2T-TTC and 2TC-TT have great potentials as a weak electron-accepting building block for wide band gap polymers for high-performance non-fullerene organic solar cells, and the carboxylate position on the polymer backbones is critical for performance improvement of organic photovoltaic devices.</P> [FIG OMISSION]</BR>

Impact of NR1I2, adenosine triphosphateebinding cassette transporters genetic polymorphisms on the pharmacokinetics of ginsenoside compound K in healthy Chinese volunteers

Luping Zhou,Lulu Chen,Yaqin Wang,Jie Huang,Guo Ping Yang,Zhi-Rong Tang,Yicheng Wang,Jianwei Liao,Gan Zhou,Kai-hua Wei,Zhenyu Li,Dongsheng Ouyang 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.3

Background: Ginsenoside compound K (CK) is a promising drug candidate for rheumatoid arthritis. Thisstudy examined the impact of polymorphisms in NR1I2, adenosine triphosphateebinding cassette (ABC)transporter genes on the pharmacokinetics of CK in healthy Chinese individuals. Methods: Forty-two targeted variants in seven genes were genotyped in 54 participants using SequenomMassARRAY system to investigate their association with major pharmacokinetic parameters of CK and itsmetabolite 20(S)-protopanaxadiol (PPD). Subsequently, molecular docking was simulated using theAutoDock Vina program. Results: ABCC4 rs1751034 TT and rs1189437 TT were associated with increased exposure of CK anddecreased exposure of 20(S)-PPD, whereas CFTR rs4148688 heterozygous carriers had the lowestmaximum concentration (Cmax) of CK. The area under the curve from zero to the time of the lastquantifiable concentration (AUClast) of CK was decreased in NR1I2 rs1464602 and rs2472682 homozygouscarriers, while Cmax was significantly reduced only in rs2472682. ABCC4 rs1151471 and CFTR rs2283054influenced the pharmacokinetics of 20(S)-PPD. In addition, several variations in ABCC2, ABCC4, CFTR, andNR1I2 had minor effects on the pharmacokinetics of CK. Quality of the best homology model of multidrugresistance protein 4 (MRP4) was assessed, and the ligand interaction plot showed the mode of interactionof CK with different MRP4 residues. Conlusion: ABCC4 rs1751034 and rs1189437 affected the pharmacokinetics of both CK and 20(S)-PPD. NR1I2 rs1464602 and rs2472682 were only associated with the pharmacokinetics of CK. Thus, thesehereditary variances could partly explain the interindividual differences in the pharmacokinetics of CK.

(Semi)ladder-Type Bithiophene Imide-Based All-Acceptor Semiconductors: Synthesis, Structure-Property Correlations, and Unipolar n-Type Transistor Performance

Wang, Yingfeng,Guo, Han,Harbuzaru, Alexandra,Uddin, Mohammad Afsar,Arrechea-Marcos, Iratxe,Ling, Shaohua,Yu, Jianwei,Tang, Yumin,Sun, Huiliang,Ló,pez Navarrete, Juan Teodomiro,Ortiz, Rocio Ponce American Chemical Society 2018 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.140 No.19

<P>Development of high-performance unipolar n-type organic semiconductors still remains as a great challenge. In this work, all-acceptor bithiophene imide-based ladder-type small molecules BTI<I>n</I> and semiladder-type homopolymers PBTI<I>n</I> (<I>n</I> = 1-5) were synthesized, and their structure-property correlations were studied in depth. It was found that Pd-catalyzed Stille coupling is superior to Ni-mediated Yamamoto coupling to produce polymers with higher molecular weight and improved polymer quality, thus leading to greatly increased electron mobility (μ<SUB>e</SUB>). Due to their all-acceptor backbone, these polymers all exhibit unipolar n-type transport in organic thin-film transistors, accompanied by low off-currents (10<SUP>-10</SUP>-10<SUP>-9</SUP> A), large on/off current ratios (10<SUP>6</SUP>), and small threshold voltages (∼15-25 V). The highest μ<SUB>e</SUB>, up to 3.71 cm<SUP>2</SUP> V<SUP>-1</SUP> s<SUP>-1</SUP>, is attained from PBTI1 with the shortest monomer unit. As the monomer size is extended, the μ<SUB>e</SUB> drops by 2 orders to 0.014 cm<SUP>2</SUP> V<SUP>-1</SUP> s<SUP>-1</SUP> for PBTI5. This monotonic decrease of μ<SUB>e</SUB> was also observed in their homologous BTI<I>n</I> small molecules. This trend of mobility decrease is in good agreement with the evolvement of disordered phases within the film, as revealed by Raman spectroscopy and X-ray diffraction measurements. The extension of the ladder-type building blocks appears to have a large impact on the motion freedom of the building blocks and the polymer chains during film formation, thus negatively affecting film morphology and charge carrier mobility. The result indicates that synthesizing building blocks with more extended ladder-type backbone does not necessarily lead to improved mobilities. This study marks a significant advance in the performance of all-acceptor-type polymers as unipolar electron transporting materials and provides useful guidelines for further development of (semi)ladder-type molecular and polymeric semiconductors for applications in organic electronics.</P> [FIG OMISSION]</BR>