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Saheed O. Oseni Olawale L. Osifeko Adenike O. Boyo Genene Tessema Mola 《应用聚合物科学杂志》2023,140(2):e53293
CdTeSe colloidal quantum dot (QD) was used to enhance photon capture in thin film polymer solar cells (TFPSC). The QDs were synthesized in aqueous media from two different precursors. Bulk heterojunction (BHJ) polymer blends composed of P3HT and PCBM were used as an absorber layer of the solar cell to investigate the effect of QDs. Different concentrations of QDs were used in the polymer matrix, which significantly impacted the power conversion efficiency (PCE) of the doped devices. More device performance growth was recorded by employing a small amount of solvent additives to disperse the QDs and increase the polymer's crystallinity in the medium. Hence, the addition of 1, Chloronaphthalene (CN) solvent additive in the QD-doped bulk heterojunction film further enhanced the overall performance of the TFPSC due to improved film morphology that has significantly influenced the charge transport processes. Consequently, the PCE of the solar cell increased by nearly 50% compared to the pristine TFPSC due to the effect of solvent additives. 相似文献
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Desta A. Gedefaw Zaifei Ma Zewdneh Genene Stefan Hellström Fengling Zhang Wendimagegn Mammo Olle Inganäs Mats R. Andersson 《Polymer International》2014,63(1):22-30
Two polymers with polar side chains, namely poly[2,7‐(9,9‐dioctylfluorene)‐alt‐5,5‐(5',8'‐di‐2‐thienyl‐(2',3'‐bis(3''‐(2‐(2‐methoxyethoxy)ethoxy)phenyl)quinoxaline))] ( P1 ) and poly[2,7‐(9,9‐bis(2‐(2‐methoxyethoxy)ethyl)fluorene)‐alt‐5,5‐(5',8'‐di‐2‐thienyl‐(2',3'‐bis(3''‐(2‐(2‐methoxyethoxy)‐ethoxy)phenyl)quinoxaline))] ( P2 ), were synthesized for solar cell application. A series of bulk heterojunction solar cells were systematically fabricated and characterized by varying the electron‐acceptor materials, processing solvents and thickness of the active layer. The results show that P1 , with a higher molecular weight and good film‐forming properties, performed better. The best device showed an open circuit voltage of 0.87 V, a short circuit current of 6.81 mA cm?2 and a power conversion efficiency of 2.74% with 1:4 polymer:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PCBM[70]) mixture using o‐dichlorobenzene (o‐DCB) as processing solvent. P2 on the other hand showed a poorer performance with chlorobenzene as processing solvent, but a much improved performance was obtained using o‐DCB instead. Thus, an open circuit voltage of 0.80 V, short circuit current of 6.21 mA cm?2 and an overall power conversion efficiency of 2.22% were recorded for a polymer:PCBM[70] mixing ratio of 1:4. This is presumably due to the improvement of the morphology of the active layer using o‐DCB as processing solvent. © 2013 Society of Chemical Industry 相似文献
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Zewdneh Genene Wendimagegn Mammo Ergang Wang Mats R. Andersson 《Advanced materials (Deerfield Beach, Fla.)》2019,31(22)
All‐polymer solar cells (all‐PSCs) based on n‐ and p‐type polymers have emerged as promising alternatives to fullerene‐based solar cells due to their unique advantages such as good chemical and electronic adjustability, and better thermal and photochemical stabilities. Rapid advances have been made in the development of n‐type polymers consisting of various electron acceptor units for all‐PSCs. So far, more than 200 n‐type polymer acceptors have been reported. In the last seven years, the power conversion efficiency (PCE) of all‐PSCs rapidly increased and has now surpassed 10%, meaning they are approaching the performance of state‐of‐the‐art solar cells using fullerene derivatives as acceptors. This review discusses the design criteria, synthesis, and structure–property relationships of n‐type polymers that have been used in all‐PSCs. Additionally, it highlights the recent progress toward photovoltaic performance enhancement of binary, ternary, and tandem all‐PSCs. Finally, the challenges and prospects for further development of all‐PSCs are briefly considered. 相似文献
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Journal of Computational Electronics - Incorporation of metal nanoparticles (NPs) into various layers of organic solar cells (OSCs) has become a popular means of enhancing device performances... 相似文献
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Efficient Near‐Infrared Electroluminescence at 840 nm with “Metal‐Free” Small‐Molecule:Polymer Blends 下载免费PDF全文
Alessandro Minotto Petri Murto Zewdneh Genene Andrea Zampetti Giuseppe Carnicella Wendimagegn Mammo Mats R. Andersson Ergang Wang Franco Cacialli 《Advanced materials (Deerfield Beach, Fla.)》2018,30(34)
Due to the so‐called energy‐gap law and aggregation quenching, the efficiency of organic light‐emitting diodes (OLEDs) emitting above 800 nm is significantly lower than that of visible ones. Successful exploitation of triplet emission in phosphorescent materials containing heavy metals has been reported, with OLEDs achieving remarkable external quantum efficiencies (EQEs) up to 3.8% (peak wavelength > 800 nm). For OLEDs incorporating fluorescent materials free from heavy or toxic metals, however, we are not aware of any report of EQEs over 1% (again for emission peaking at wavelengths > 800 nm), even for devices leveraging thermally activated delayed fluorescence (TADF). Here, the development of polymer light‐emitting diodes (PLEDs) peaking at 840 nm and exhibiting unprecedented EQEs (in excess of 1.15%) and turn‐on voltages as low as 1.7 V is reported. These incorporate a novel triazolobenzothiadiazole‐based emitter and a novel indacenodithiophene‐based transport polymer matrix, affording excellent spectral and transport properties. To the best of knowledge, such values are the best ever reported for electroluminescence at 840 nm with a purely organic and solution‐processed active layer, not leveraging triplet‐assisted emission. 相似文献
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Genene Tessema Mulugeta Bekele Reiner Vianden 《Journal of Materials Science: Materials in Electronics》2010,21(11):1144-1148
The formation of germanium-carbide in crystalline germanium substrate is studied using the perturbed γ–γ angular correlation
(PAC) method. The growth of Ge–C micro-crystalline system in the host matrix was observed after annealing the sample above
450°C in vacuum. The Ge–C complexes have been detected at high dose carbon implantation in germanium (≥1 × 1015cm −2). Information about the lattice locations of the carbon atoms in the host lattice can be obtained via the interaction between
carbon atoms with unstable probe nucleus (111In). Several carbon related complexes have been detected in this investigations which can be characterized by unique quadrupole
interaction frequencies. The parameters of the hyperfine interactions drawn from the time spectra provide additional information
about the formation of Ge–C system in germanium. 相似文献
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Sharma Shweta Sharma Gaurav Kumar Amit Naushad Mu. Mola Genene Tessema Kumar Anuj Al-Misned Fahad A. El-Serehy Hamed A. Stadler Florian J. 《Topics in Catalysis》2020,63(11-14):1302-1313
Topics in Catalysis - The water management sector is becoming extremely challenging these days because of poor water quality which is due to the presence of noxious pollutants at an... 相似文献
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