Search results
Results from the WOW.Com Content Network
The proton-exchange membrane is commonly made of materials such as perfluorosulfonic acid (PFSA, sold commercially as Nafion and Aquivion), which minimize gas crossover and short circuiting of the fuel cell. A disadvantage of fluor containing polymers is the fact that during production (and disposal) PFAS products are formed.
A proton-exchange membrane, or polymer-electrolyte membrane (PEM), is a semipermeable membrane generally made from ionomers and designed to conduct protons while acting as an electronic insulator and reactant barrier, e.g. to oxygen and hydrogen gas. [1]
The following other wikis use this file: Usage on ca.wikipedia.org Pila de combustible de membrana d'intercanvi de protons; Usage on fa.wikipedia.org
Electro-chemical reaction Diagram of PEM MEA. A membrane electrode assembly (MEA) is an assembled stack of proton-exchange membranes (PEM) or alkali anion exchange membrane (AAEM), catalyst and flat plate electrode used in fuel cells and electrolyzers. [1] [2]
Proton exchange membrane (PEM) electrolysis is the electrolysis of water in a cell equipped with a solid polymer electrolyte (SPE) [3] that is responsible for the conduction of protons, separation of product gases, and electrical insulation of the electrodes. The PEM electrolyzer was introduced to overcome the issues of partial load, low ...
Whereas the common PEM fuel cell, also called Low Temperature Proton Exchange Membrane fuel cell (LT-PEM), must usually be operated with hydrogen with high purity of more than 99.9 % the HT-PEM fuel cell is less sensitive to impurities and thus is typically operated with reformate gas with hydrogen concentration of about 50 to 75 %.
Transport of the positively charged proton is typically electrogenic, i.e.: it generates an electric field across the membrane also called the membrane potential.Proton transport becomes electrogenic if not neutralized electrically by transport of either a corresponding negative charge in the same direction or a corresponding positive charge in the opposite direction.
The DCT is lined with simple cuboidal cells, the distal convoluted tubule cells, that are shorter than those of the proximal convoluted tubule (PCT). The lumen appears larger in the PCT than the DCT lumen because the PCT has a brush border (microvilli).