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71.
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
72.
Synthesis of gold nanoparticles decorated on sulfonated three‐dimensional graphene nanocomposite and application as a highly efficient and recyclable heterogeneous catalyst for Ullmann homocoupling of aryl iodides and reduction of p‐nitrophenol
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Minoo Dabiri Seyede Razie Banifatemi Kashi Noushin Farajinia Lehi Sahareh Bashiribod 《应用有机金属化学》2018,32(3)
Gold nanoparticles were decorated onto sulfonated three‐dimensional graphene (3DG‐SO3H) through spontaneous chemical reduction of HAuCl4 by 3DG‐SO3H. This nanocomposite exhibited excellent catalytic activity for the synthesis of symmetric biaryls via the Ullmann homocoupling of aryl iodides in an aqueous medium. Additionally, this nanocomposite was used as a catalyst for the reduction of p‐nitrophenol to p‐aminophenol. The catalyst could be used more than six times successively without significant deactivation. 相似文献
73.
Róbert Rajkó Samira Beyramysoltan Hamid Abdollahi János Eőri Gábor Pongor 《Analytica chimica acta》2015
In this paper the authors have investigated spectroscopic data analysis according to a recent development, i.e. the Direct Inversion in the Spectral Subspace (DISS) procedure. 相似文献
74.
75.
A combination of HBr and trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane as anew and powerful oxidant was found effective for facile brotnination of different aromatic compounds at room temperature in water as a green solvent.Mild reaction conditions,high selectivity and yield,high reaction rate and non-toxicity are some of the major advantages of this synthetic protocol. 相似文献
76.
77.
Sayed A.M. Marzouk Mohamed H. Al-Marzouqi Samira M.S.M. Baomran 《Microchemical Journal》2010,95(2):207-212
The construction, optimization and use of simple and inexpensive gas analyzer for real time measurement of sulfur dioxide in gas streams are described. The analyzer consisted of three main components (i) a custom fabricated hollow fiber membrane (HFM) gas contactor, (ii) carrier solution which absorbs SO2 molecules from the gas stream in the HFM gas contactor and (iii) a flow-through detector placed downstream which continuously measures the changes occurred to the carrier solution upon absorption of SO2 molecules. The significant acidic properties of the produced sulfurous acid suggested pH and conductivity detectors to monitor the decrease in pH or the increase in the conductivity which constituted the basis for quantification of SO2 in the gas line. Aqueous potassium oxalate (10? 1 mol/L) and hydrogen peroxide (10? 3 mol/L) were used as carrier solutions in combination with pH and conductivity detectors, respectively. The analyzer equipped with pH detector provided linear potentiometric response to SO2 concentration up to 1000 ppm with Nernstian slop of 61 mV/log[SO2]. Excellent SO2 recoveries (97–108%) were obtained in the presence of several folds of potentially interfering acidic gases, i.e., CO2 and H2S. The conductivity detector provided linear response up to 2500 ppm. Under optimized conditions, both detectors offered several favorable performance characteristics such as (i) fast response and recovery times, (ii) excellent signal stability and reproducibility (RSD = 0.5%), (iii) intrinsic high selectivity to most common neutral gases, e.g., CH4, N2, O2, CO, etc. The suggested analyzer was applied successfully in monitoring the removal of SO2 from SO2–N2 gas mixtures with hollow fiber membrane contactor using distilled water or aqueous sodium hydroxide as stripping solvents. 相似文献
78.
MP2/aug-cc-pVTZ calculations were carried out on complexes wherein the proton or the lithium cation is located between π-electron systems, or between π-electron and σ-electron units. The acetylene or its fluorine and lithium derivatives act as the Lewis base π-electron species similarly to molecular hydrogen, which acts as the electron donor via its σ-electrons. These complexes may be classified as linked by π-H∙∙∙π/σ hydrogen bonds and π-Li∙∙∙π/σ lithium bonds. The properties of these interactions are discussed, and particularly the Lewis acid units are analyzed, because multi-center π-H or π-Li covalent bonds may occur in these systems. Various theoretical approaches were applied here to analyze the above-mentioned interactions—the Quantum Theory of Atoms in Molecules (QTAIM), the Symmetry-Adapted Perturbation Theory (SAPT) and the Non-Covalent Interaction (NCI) method. 相似文献
79.
Iran Sheikhshoaie Hojatollah Khabazzadeh Samira Saeid-Nia 《Transition Metal Chemistry》2009,34(5):463-466
[Fe(III)(salen)]Cl (salen = N,N′-ethylenebis(salicylimine)) is an efficient catalyst for the electrophilic substitution of
indole with carbonyl compounds to afford the corresponding bis(indolyl)methanes in good yields in molten tetrabutylammonium
bromide as an ionic liquid. Notable features of this new procedure are shorter reaction times, cleaner reaction profiles,
and simple experimental and work-up procedures. 相似文献
80.
Samira Ceccarelli Jakub Wenus Maurice S. Skolnick David G. Lidzey 《Superlattices and Microstructures》2007,41(5-6):289
We investigated the absorption and photoluminescence (PL) of J-aggregates of a cyanine dye both in a thin film format and when used as the active layer in a strongly-coupled microcavity. We show that as temperature is reduced, the absorption linewidth of the J-aggregates narrows and shifts to higher energy. When the J-aggregate is placed in a microcavity we find that the energy of the polariton modes also shifts to higher energies as temperature is reduced. We compare the intensity of PL emission from the upper and lower branches at resonance as a function of temperature, and find that it can be described by an activation energy of 25 meV. PL emission spectra at resonance also suggest that uncoupled excitons inside the microcavity populate the upper polariton branch states. 相似文献