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501.
A New D–A conjugated polymer P(PTQD‐BDT) with PTQD acceptor and BDT donor units for BHJ polymer solar cells application 下载免费PDF全文
M. L. Keshtov S. A. Kuklin F. C. Chen A. R. Khokhlov Rajnish Kurchania G. D. Sharma 《Journal of polymer science. Part A, Polymer chemistry》2015,53(20):2390-2398
A novel donor–acceptor ( D–A ) copolymer comprising of weak electron donating BDT moiety and strong 9‐(2‐octyldodecyl)?8H‐pyrrolo[3,4‐b] bisthieno[2,3‐f:3',2'‐h] quinoxaline‐8,10(9H)‐dione (PTQD) unit denoted as P(PTQD‐BDT) was synthesized as donor material for polymer solar cells. P(PTQD‐BDT) shows a broad visible‐near‐infrared absorption band with an optical bandgap of 1.74 eV and possesses a relatively low‐lying HOMO level at ?5.28 eV. Bulk‐heterojunction polymer solar cell with the optimized blend of 1:2 (weight ratio) P(PTQD‐BDT):PC71BM (processed with chloroform) shows an open circuit voltage of 0.92 V, a short circuit current density of 7.84 mA/cm2, and a fill factor of 0.50, achieving a power conversion efficiency (PCE) of 3.61%. The PCE has been further improved to 5.55 % (Jsc = 10.34 mA/cm2, Voc = 0.88V and FF = 0.61), when 3% v ol 1,8‐diio‐dooctane (DIO) was used as solvent additive for the processing of P(PTQD‐BDT):PC71BM blended film. The enhancement in Jsc is as a result of the appropriate morphology and efficient exciton dissociation into free charge carrier. The increase in PCE has been attributed to the favorable nanoscale morphology for efficient exciton dissociation and charge transport (reduction in the electron to hole mobility ratio). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2390–2398 相似文献
502.
Two-dimensional materials have attracted great attention because of their ultra-thin atomic layer thickness and high carrier mobility. In this work, we investigated the electronic transport of in-plane (IP) heterojunction based on Cu/Blue Phosphorus (BlueP), and the results suggest the metallization at the IP Cu/BlueP contact interface and a small Schottky barrier. Then, we investigated the performance of 5.1 nm IP BlueP Schottky barrier field-effect transistors (SBFET) with different dielectrics (SiO2, Al2O3, Y2O3, and La2O3) using quantum transport simulations. The results show that IP BlueP SBFETs with four dielectrics satisfy the off-state requirement of the International Technology Roadmap for Semiconductors (ITRS) for the high-performance (HP) device. However, the on-state current of only IP BlueP SBFET with La2O3 satisfies the requirements of ITRS. This will provide a reference for designing BlueP SBFETs. 相似文献
503.
Ming-Yang Li Hang Yin Ming-Yue Sui Fei Wang Yan-Hui Liu Guang-Yan Sun 《International journal of quantum chemistry》2019,119(15):e25938
The charge transfer (CT) mechanism at the donor/acceptor (D/A) interface plays an irreplaceable role in the photoelectric conversion of efficient bulk-heterojunction (BHJ) organic solar cells (OSCs), which affects the resulting competition between charge separation and charge recombination. Extensive CT studies have preferred monoadduct fullerene derivatives ( M60 , M70 ) due to their unique spherical geometry with fewer factors to consider. However, the effect of carbon cage size, substituent group properties and the number of CT properties have not been much discussed. Here, sulfur-containing bisadducts ( B60 , B70 ) were selected to explore whether they are also suitable for CT research like classical monoadducts. Using density functional theory and time-dependent density functional theory, interface stacking configuration, key parameters relevant to CT states, charge separation, and recombination rates were determined to confirm the characteristics of B60 and B70 as a good acceptor applied to interfacial research. This work points to the CT mechanism along the route of DA → D*A → D+A− through a theoretical analysis and also provides candidates for the theoretical interface photoelectric process in BHJ OSCs: bisadduct fullerene derivatives as good acceptor materials. 相似文献
504.
Comprehensive study of pyrido[3,4‐b]pyrazine‐based D–π–a copolymer for efficient polymer solar cells 下载免费PDF全文
Yun‐Siou Yang Sheng Hsiung Chang Pin‐Jiun Wu Yen‐Yi Chu Chun‐Guey Wu 《Journal of polymer science. Part A, Polymer chemistry》2016,54(12):1822-1833
Two D–π–A copolymers, based on the benzo[1,2‐b:4,5‐b′]‐dithiophene (BDT) as a donor unit and benzo‐quinoxaline (BQ) or pyrido‐quinoxaline (PQ) analog as an acceptor (PBDT‐TBQ and PBDT‐TPQ), were designed and synthesized as a p‐type material for bulk heterojunction (BHJ) photovoltaic cells. When compared with the PBDT‐TBQ polymer, PBDT‐TPQ exhibits stronger intramolecular charge transfer, showing a broad absorption coverage at the red region and narrower optical bandgap of 1.69 eV with a relatively low‐lying HOMO energy level at ?5.24 eV. The experimental data show that the exciton dissociation efficiency of PBDT‐TPQ:PC71BM blend is better than that in the PBDT‐TBQ:PC71BM blend, which can explain that the IPCE spectra of the PBDT‐TPQ‐based solar cell were higher than that of the PBDT‐TBQ‐based solar cell. The maximum efficiency of PBDT‐TPQ‐based device reaches 4.40% which is much higher than 2.45% of PBDT‐TBQ, indicating that PQ unit is a promising electron‐acceptor moiety for BHJ solar cells. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1822–1833 相似文献
505.
半导体异质结光催化剂因其在太阳能利用和转化方面广阔的应用前景而备受关注。合理构建两种或两种以上半导体材料的异质结构,可以集成多种组分的优点,改善光生电荷分离,扩大对可见光的吸收范围,保持光催化剂的高氧化还原能力。近年来,由于g-C3N4具有合成简单、稳定性高、独特的光学和电学特性等诸多优点,g-C3N4基异质结构的构建成为研究热点。本文针对近年来g-C3N4基异质结改性的研究现状,依据g-C3N4与其他半导体电荷转移路径的不同综述了三种异质结结构(g-C3N4基Ⅱ型异质结、g-C3N4基Z型异质结和g-C3N4基S型异质结),以及其在环境修复和能源方面的应用。最后对g-C3N4基异质结光催化剂存在的问题进行总结和展望。 相似文献
506.
507.
Y.S. Kim Y. Lee Wonjoo Lee Hanok Park Sung-Hwan Han Soo-Hyoung Lee 《Current Applied Physics》2010,10(1):329-332
This paper reports the effect of the molecular weight (MW) and polydispersity (PD) of poly (3-hexylthiophene) (P3HT) in bulk heterojunction polymer solar cells (BHJ-SCs). The P3HT with low MW and broad PD exhibited higher crystallinity compared to that with high MW and narrow PD. Due to the improved crystallinity, the BHJ-SCs based on P3HT with low MW and broad PD showed performance with a power conversion efficiency of 3.8% with short-circuit currents of −9.90 mA/cm2. 相似文献
508.
Interfacial barrier is a key factor that determines the performances of heterojunctions.In this work,we study the effect of manganite film thickness on the effective interfacial barrier for La 0.67 Sr 0.33 MnO 3 /Nb:SrTiO 3 junctions.The barrier is extracted from the forward current-voltage characteristics.Our results demonstrate that the barrier decreases gradually from ~0.85 eV to ~0.60 eV when the film thickness decreases from 150 nm to 2 nm.The overall value of the barrier is only about 50% of the corresponding one determined from the photovoltaic effect. 相似文献
509.
Searching for high-performance and cost-effective catalysts is of particular importance for the practical electrocatalysis applications. The heterojunctions with components in different dimensions show unique physical and chemical properties, which can offer large space for rational design of electrocatalysts. In this paper, we firstly reviewed recently related works, and then proposed a few perspectives on exploring heterojunction for electrocatalysis applications. 相似文献
510.
《Current Applied Physics》2014,14(3):340-344
We present an analytical model for bulk heterojunction organic solar cells incorporating the physics of recombination in the transport equations. Monomolecular recombination process is considered to be the dominant mechanism and treated explicitly. The proposed analytical model shows good agreement with the experimental data as well as with the numerical simulations. The improvements over the previous models are also presented to show the importance of considering the recombination process. The model can be used to find device characteristics such as current–voltage characteristic, efficiency etc. of bulk heterojunction organic solar cells avoiding the mathematical complexities of numerical models. 相似文献