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Metal Cathodes (metal + cathode)
Selected AbstractsWater-Soluble Polyfluorenes as an Interfacial Layer Leading to Cathode-Independent High Performance of Organic Solar CellsADVANCED FUNCTIONAL MATERIALS, Issue 12 2010Seung-Hwan Oh Abstract Novel poly[(9,9-bis((6,-(N,N,N -trimethylammonium)hexyl)-2,7-fluorene)- alt -(9,9-bis(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-9-fluorene)) dibromide (WPF-6-oxy-F) and poly[(9,9-bis((6,-(N,N,N -trimethylammonium)hexyl)-2,7-fluorene)- alt -(9,9-bis(2-(2-methoxyethoxy)ethyl)-fluorene)] dibromide (WPF-oxy-F) compounds are developed and the use of these water-soluble polymers as an interfacial layer for low-cost poly(3-hexylthiophene):phenyl-C61 butyric acid methyl ester (P3HT:PCBM) organic solar cells (OSCs) is investigated. When WPF-oxy-F or WPF-6-oxy-F is simply inserted between the active layer and the cathode as an interfacial dipole layer by spin-coating water-soluble polyfluorenes, the open-circuit voltage (Voc), fill factor (FF), and power-conversion efficiency (PCE) of photovoltaic cells with high work-function metal cathodes, such as Al, Ag, Au, and Cu, dramatically increases. For example, when WPF-6-oxy-F is used with Al, Ag, Au, or Cu, regardless of the work-function of the metal cathode, the Voc is 0.64, 0.64, 0.58, and 0.63,V, respectively, approaching the original value of the P3HT:PCBM system because of the formation of large interfacial dipoles through a reduction of the metal work-function. In particular, introducing WPF-6-oxy-F into a low-cost Cu cathode dramatically enhanced the device efficiency from 0.8% to 3.36%. [source] Fabrication of Reversely Tapered Three-Dimensional Structures and Their Application to Organic Light-Emitting DiodesADVANCED MATERIALS, Issue 13 2003J. Rhee Cathode separators typically used for patterning metal cathodes of organic light-emitting diodes (OLEDs),see Figure,can be fabricated using a lithography-based technique that allows the construction of reversely tapered 3D structures in one single molding step. The physics involved in making the fabrication of such 3D structures possible is outlined and the efficacy of the separator thus fabricated is demonstrated with an OLED. [source] Operating and scale-up factors for the electrolytic removal of algae from eutrophied lakewaterJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2002Catalino G Alfafara Abstract Electrolytic removal of algae was conducted in batch and continuous reactors to investigate operating factors affecting removal efficiency and to explore engineering relationships which could be useful for operation and scale-up. The system integrated both electro-flocculation and electro-flotation mechanisms by using polyvalent metal anodes and inert metal cathodes. Batch reactor studies confirmed that high electrical input power or higher electrical current achieved higher and faster removal efficiencies. Natural liquid circulation was observed during electrolytic operation and increased with higher electrical power. However, a small degree of external mixing may be useful at lower electrical power input. Electro-flotation alone could not achieve complete algae removal (maximum efficiency 40,50%), and showed the importance of algal floc formation for the complete removal of algae. In continuous electrolysis experiments, the ratio of the volumetric current intensity (amperes,dm,3) and the chlorophyll a loading (mg,dm,3,h,1) was found to be a useful operating and scale-up factor to balance high algal removal efficiency with minimum release of excess aluminum. This ratio was eventually found to be just the charge dose or the amount of coulombs required to remove a unit mass of chlorophyll a. The optimum charge dose was determined and used to relate the operating current and electrolysis time of a continuous process. © 2002 Society of Chemical Industry [source] | ||||||||||