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Enhanced properties of photovoltaic devices tailored with novel supramolecular structures based on reduced graphene oxide nanosheets grafted/functionalized with thiophenic materials
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Samira Agbolaghi Sara Ebrahimi Bakhshali Massoumi Saleheh Abbaspoor Raana Sarvari Farhang Abbasi 《Journal of Polymer Science.Polymer Physics》2017,55(24):1877-1889
For verifying the influence of donor–acceptor supramolecules on photovoltaic properties, different hybrids were designed and used in organic solar cells. In this respect, reduced graphene oxide (rGO) was functionalization with 2‐thiophene acetic acid (rGO‐f‐TAA) and grafted with poly(3‐dodecylthiophene) (rGO‐g‐PDDT) and poly(3‐thiophene ethanol) (rGO‐g‐PTEt) to manipulate orientation of poly(3‐hexylthiophene) (P3HT) assemblies. Face‐on, edge‐on, and flat‐on orientations were detected for assembled P3HTs on rGO and its functionalized and grafted derivatives, respectively. Alteration of P3HT orientation from face‐on to flat‐on enhanced current density (J sc), fill factor (FF), and power conversion efficiency (PCE) and thus J sc = 7.11 mA cm?2, FF = 47%, and PCE = 2.14% were acquired. By adding phenyl‐C71‐butyric acid methyl ester (PC71BM) to active layers composed of pre‐designed P3HT/rGO, P3HT/rGO‐f‐TAA, P3HT/rGO‐g‐PDDT, and P3HT/rGO‐g‐PTEt hybrids, photovoltaic characteristics further improved, demonstrating that supramolecules appropriately mediated in P3HT:PC71BM solar cells. Phase separation was more intensified in best‐performing photovoltaic systems. Larger P3HT crystals assembled onto grafted rGOs (95–143 nm) may have acted as convenient templates for the larger and more intensified phase separation in P3HT:PCBM films. The best performances were reached for P3HT:P3HT/rGO‐g‐PDDT:PCBM (J sc = 9.45 mA cm?2, FF = 54%, and PCE = 3.16%) and P3HT:P3HT/rGO‐g‐PTEt:PCBM (J sc = 9.32 mA cm?2, FF = 53%, and PCE = 3.11%) photovoltaic systems. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55 , 1877–1889 相似文献
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Structural Chemistry - Acidity changes of p-aminobenzoic acid (pABA) after π-stacking with substituted benzenes (SB) have been investigated using quantum mechanical calculations at the... 相似文献
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Farzaneh Tajfirooz Abolghasem Davoodnia Mehdi Pordel Mahmoud Ebrahimi Amir Khojastehnezhad 《应用有机金属化学》2018,32(1)
New functionalized magnetic core–shell nanoparticles, CuFe2O4@SiO2‐OP2O5H, were prepared by grafting of phosphorus pentoxide on CuFe2O4@SiO2 nanoparticles and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, energy‐dispersive X‐ray analysis, inductively coupled plasma optical emission spectrometry and vibrating sample magnetometry. The catalytic activity of CuFe2O4@SiO2‐OP2O5H as a novel catalyst was evaluated in the synthesis of 1,8‐dioxo‐octahydroxanthenes under solvent‐free conditions. The results showed that the catalyst has high activity and the desired products are obtained in high yields within short reaction times. The catalyst is readily recovered using magnetic decantation and can be used at least four times without noticeable deterioration in catalytic activity. 相似文献
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It is known that although the Baer Criterion for injectivity holds for modules over rings with unit, it is not true for acts over an arbitrary monoid. Seeking a characterization for the Baer Criterion to hold for acts over a monoid, in this article, using the notion of completeness introduced by Giuli, we find some classes of monoids such that for acts over them the Baer Criterion holds. 相似文献
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Nona Habibi Mahmoud Ebrahimi 《International journal of environmental analytical chemistry》2013,93(14):1459-1470
ABSTRACTA novel ion-selective electrochemical sensor based on kryptofix-22DD (1,10-didecyl-1,10-diaza-18-crown-6) as an ionophore was constructed for determination of lanthanum(III) cation in solutions. The D-Optimal Mixture Design(D-OMD) was used as an experimental design strategy for optimal formulation of the membrane ingredients, and the actual values of the ingredients were compared with their predicted values. The amounts of the ionophore, plasticizer, PVC, and also the graphite powder which influence the performance of the fabricated electrode were analyzed using D-OMD. A non-linear relationship was observed between the slope of the electrochemical response of the electrode and these variables and the interaction between the variables as well. The experimental results showed that the amount of the ionophore has the most positive effect on the electrochemical response of the electrode. The constructed electrode exhibits a Nernstian slope (20.60 ± 0.21 mv.decade?1) in a wide linear concentration range from 1.0 × 10?7 to 1.0 × 10?1 M with respect to La3+ cation at pH range of 4.0 to 6.0, and its detection limit was found to be:0.8 × 10?7M. The selectivity of the proposed electrode towards some of the metal cations present in lanthanum(III) cation solutions was tested, and the experimental results showed a good selectivity towards this metal cation. 相似文献
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In this work nanocrystalline BaFe12O19 thin films have been prepared on the Si (1 1 0) substrates by a sol–gel method using the aqueous solution of metal nitrates. The efforts have been done to decrease the calcination temperature and to reduce the crystallite size of the single-phase barium ferrite thin films. The precursor solutions were primed with the various Fe/Ba ratios and two kinds of the basic agents, and the coated films were heat treated at the different temperatures. The thin films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The effects of calcination temperature, molar ratio of Fe/Ba and basic agent on composition, crystallites size and morphology were also investigated. 相似文献
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