PDF Publication Title:
Text from PDF Page: 018
Chapter 1 Introduction Because of this water filled network in a hydrophobic backbone, protons can be transported through these channels in H3O+ form by Grotthuss dif- fusion (i.e. proton hopping). In this mechanism, a proton connects to a wa- ter molecule to form H3O+. Therefore, the membranes have to be hydrated. On the other side of the hydride ion, one of the other protons is released, which can form a bond with the next water molecule. In this way the acid group can diffuse very fast. A schematic of this process can be seen in Fig- ure 6. This mechanism explains the high proton conductivity of perfluorinated membranes. Also, the strong electrostatic interactions of the ionic clusters cause the high mechanical stability of the membrane. HHHHHHHHH + O O O O H+ O O O O 1 2 3 4 1 23 4 rotation jump HHHHHHHHH + O O O O -H+ O O O O 1 23 4 1 23 4 Figure 6. Grotthuss mechanism (adapted from [12]). Proton transport through the membrane shows the same characteristics as in an aqueous solution. For every proton a shell of water is also transported through the membrane because of the electroosmotic water drag through the cell. Another factor influencing the water uptake in a membrane is the back diffusion of product water from the cathode into the membrane. A big disadvantage of Nafion® for the DMFC application is the high metha- nol cross-over. The high methanol permeability reduces the efficiency of a DMFC substantially. Methanol permeation is associated with the high water content and the proton conduction mechanism [13]. This is because water and methanol can also be transported easily through the hydrophilic re- gions. Methanol crossover can be reduced by increasing the thickness or EW of the membrane, but this leads to higher voltage losses especially at 10PDF Image | Development of membrane materials for direct methanol fuel cells
PDF Search Title:
Development of membrane materials for direct methanol fuel cellsOriginal File Name Searched:
thesis_H_Yildirim.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)