What are anion exchange membranes (AEMs) commonly used for?
AEMs can be used for fuel cells, redox flow batteries, electrolyzers, and water desalination membranes.
Why are AEMs considered attractive as an electrolyte layer?
AEMs are attractive due to their low cost and ease of manufacturing compared to PEM membranes.
What is the previous version of the AEMFC?
The previous version of the AEMFC is the AFC, which used a liquid alkaline electrolyte matrix and was used in NASA's space missions.
What are AEMs usually made of?
AEMs are usually composed of polymers that are covalently bonded to different types of cations, such as quaternary ammonium cations, sulfonium types, imidazoliums, phosphoniums, etc.
How does ion transport occur in an electrolyte?
Ion transport can occur through diffusion, convection, or migration driven by an electrical potential across the electrolyte.
What is Grotthus transport?
Grotthus transport is the migration of protons due to interconversion between tri-coordinated H3O+(H2O)3 and H5O2+ via hydrogen bond breaking and formation.
Why is the mobility of hydroxide lower than that of protons?
The currently accepted explanation for the lower mobility of hydroxide is that it is hyper-coordinated by 4.5 water molecules, while protons are hypocoordinated by only 3 water molecules.
What experimental techniques have been used to study ion transport mechanisms?
Neutron and X-ray scattering experiments have observed the hyper-coordinated OH- complex, while FTIR spectroscopy data supports the existence of a weak hydrogen bond between OH- and H2O.
What is generally agreed upon about hydroxide transport?
While the detailed mechanisms are not fully understood, it is generally agreed that water solvation plays a critical role in the efficient migration of the hydroxide anion.
Home