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排序方式: 共有251条查询结果,搜索用时 703 毫秒
241.
Shaowei Shi Keli Shi Rui Qu Zupan Mao Hanlin Wang Gui Yu Xiaoyu Li Yongfang Li Haiqiao Wang 《Macromolecular rapid communications》2014,35(21):1886-1889
In this article, a versatile 2‐D conjugated polymer, PNDTP‐DPP, containing alkylphenyl substituted naphthodithiophene is synthesized and characterized. PNDTP‐DPP exhibits good solubility and crystallinity with a π−π stacking distance of ≈3.7 Å. Investigation of polymer solar cells (PSCs) and organic field‐effect transistors (OFET) demonstrates a promising power conversion efficiency (PCE) of 4.11% and a high hole mobility of up to 0.86 cm2 V–1 s–1, so this is one of the few examples of versatile polymers that show both good field‐effect mobility and PCE.
242.
243.
Polymer solar cells (PSCs) are composed of a blend film of a conjugated polymer donor and a soluble fullerene derivative acceptor sandwiched between a PEDOT?:?PSS coated ITO positive electrode and a low workfunction metal negative electrode. The conjugated polymer donor and the fullerene derivative acceptor are the key photovoltaic materials for high performance PSCs. For the acceptors, although [6,6]-phenyl-C(61)-butyric acid methyl ester (PC(60)BM) and its corresponding C(70) derivative PC(70)BM are dominantly used as the acceptors in PSC at present, several series of new fullerene derivatives with higher-lying LUMO energy level and better solubility were reported in recent years for further improving the power conversion efficiency of the PSCs. In this perspective paper, we reviewed the recent research progress on the new fullerene derivative acceptors, including various PC(60)BM-like C(60) derivatives, PC(60)BM bisadduct, PC(70)BM bisadduct, indene-C(60) bisadduct and indene-C(70) bisadduct, trimetallic nitride endohedral fullerenes and other C(60) derivatives with multi side chains. The synthesis and physicochemical properties of PC(60)BM and PC(70)BM were also introduced considering the importance of the two fullerene acceptors. 相似文献
244.
Zhang ZG Min J Zhang S Zhang J Zhang M Li Y 《Chemical communications (Cambridge, England)》2011,47(33):9474-9476
A new copolymer of dithienosilole and dithienylthiazolo[5,4-d]thiazole with a hexyl side chain on the 4-position of thiophene units was designed and synthesized. Polymer solar cells based on the polymer as a donor and PC(70)BM as an acceptor demonstrated a power conversion efficiency up to 5.88% with a high fill factor of 71.6%. 相似文献
245.
Cui C Fan X Zhang M Zhang J Min J Li Y 《Chemical communications (Cambridge, England)》2011,47(40):11345-11347
A strong electron-withdrawing unit, naphtho[2,3-c]thiophene-4,9-dione, was copolymerized with dithienosilole to get a D-A copolymer, PDTSNTDO, with a narrow bandgap and lower-lying HOMO level. The PCE of the PDTSNTDO-based device reached 5.21%, with a high open circuit voltage of 0.88 V. 相似文献
246.
Huang Y Huo L Zhang S Guo X Han CC Li Y Hou J 《Chemical communications (Cambridge, England)》2011,47(31):8904-8906
A strong electron-withdrawing group, sulfonyl, was firstly introduced to a semiconducting polymer, PBDTTT-S. The PCE of the PBDTTT-S device reached 6.22% with a high open-circuit voltage of 0.76 V. The sulfonyl group is thus a promising candidate as a strong electron-withdrawing group applied to high-efficiency PSCs. 相似文献
247.
A planar benzodithiophene with lower HOMO was copolymerized with the thieno[3,4-b]thiophene unit to obtain a new low band gap polymer of PBDPTT-C, which exhibited a higher open-circuit voltage (V(oc)) of 0.8 V and a promising efficiency of 5.2%. 相似文献
248.
A simple, low toxic, sensitive strategy based on the localized surface plasmon resonance light scattering (LSPR-LS) properties of silver nanoparticles (AgNPs) is introduced for the detection of gallic acid (GA). It was found that the silver ammonium complex, [Ag(NH(3))(2)](+)(aq), could be reduced in the alkaline medium by GA at room temperature; this reaction formed dispersed AgNPs. Transmission electron microscopy analyses were performed to ascertain the formation of AgNPs. UV-visible spectra revealed the localized surface plasmon resonance (LSPR) absorption at 410 nm corresponding to the LSPR of AgNPs. On these basis, we could quantify the GA concentration in the range of 4 × 10(-7) - 5 × 10(-6) mol L(-1) in the optimized experimental conditions. This method was used for determining the concentration of GA in artificial samples with satisfactory results. The detailed mechanism underlying this special phenomenon was elucidated. 相似文献
249.
Zhang Y Jiang L Li H Fan L Hu W Wang C Li Y Yang S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(17):4921-4926
Large-scale single-crystalline hollow nanobowls of pure C(60) were prepared by applying a sonophysical strategy in a binary organic solution. Through the simple adjustment of the concentration of the C(60) /m-xylene solution and the volume ratio of m-xylene to acetonitrile, C(60) nanorings, nanoplates, nanorods, and nanowires were also selectively synthesized. The promise of the C(60) hollow structures as Pt catalyst supports is heightened by the significantly enhanced catalytic activity toward methanol oxidation for a given amount of C(60) used, which demonstrates their potential application in fuel cells. 相似文献
250.
Hongyuan Fu Ming Zhang Dr. Youdi Zhang Qingyuan Wang Zheng'ao Xu Dr. Qiuju Zhou Zhengkai Li Yang Bai Prof. Yongfang Li Prof. Zhi-Guo Zhang 《Angewandte Chemie (International ed. in English)》2023,62(35):e202306303
The operational stability of polymer solar cells is a critical concern with respect to the thermodynamic relaxation of acceptor-donor-acceptor (A-D-A) or A-DA'D-A structured small-molecule acceptors (SMAs) within their blends with polymer donors. Giant molecule acceptors (GMAs) bearing SMAs as subunits offer a solution to this issue, while their classical synthesis via the Stille coupling suffers from low reaction efficiency and difficulty in obtaining mono-brominated SMA, rendering the approach impractical for their large-scale and low-cost preparation. In this study, we present a simple and cost-effective solution to this challenge through Lewis acid-catalyzed Knoevenagel condensation with boron trifluoride etherate (BF3 ⋅ OEt2) as catalyst. We demonstrated that the coupling of the monoaldehyde-terminated A-D-CHO unit and the methylene-based A-link-A (or its silyl enol ether counterpart) substrates can be quantitatively achieved within 30 minutes in the presence of acetic anhydride, affording a variety of GMAs connected via the flexible and conjugated linkers. The photophysical properties was fully studied, yielding a high device efficiency of over 18 %. Our findings offer a promising alternative for the modular synthesis of GMAs with high yields, easier work up, and the widespread application of such methodology will undoubtedly accelerate the progress of stable polymer solar cells. 相似文献