What are the two main types of membranes used in fuel cells?
Proton exchange membrane (PEM) and anion exchange membrane (AEM).
What is a bipolar membrane (BPM)?
BPM is a combination of PEM and AEM that allows both positive and negative ions to be transported simultaneously during operation.
What are some applications of BPM in the chemical industry?
Salt electrolysis, separation of mono- and divalent ions, anti-fouling, anti-deposition, water dissociation, waste recovery, and cleaning products.
What are the advantages of using BPM in fuel cells?
Each electrode can have an optimum pH, splitting, and water generation at the cation/anion interfaces.
What factors affect the behavior of BPM?
The bipolar junction structure between the anion and cation exchange membranes, and the nature of charge groups attached to the polymer matrix.
How does a BPMFC work?
Hydrogen fuel is fed to the anode side while oxygen fuel is fed to the cathode side. The hydrogen atom flows through the anode electrode, separating into proton and electron. The proton flows across the CEM toward the junction layer, while the electron flows to the external circuit. At the cathode side, oxygen reduction reaction occurs, producing hydroxide ions that flow through the AEM toward the junction layer. At the junction layer, hydrogen ions react with hydroxide ions to produce water.
What is the role of electro-osmotic drag (EOD) and diffusion mechanism in BPMFC?
They play important roles in the transportation of water molecules for hydrating the membranes.
What factors influence net water transport in BPMFC?
Properties of the coupling membranes, local relative humidity, and electric potential.
How can water management and cell performance be enhanced in BPMFC?
By modifying the BPM fabrication procedures, such as membrane thickness and water uptake properties, and its pattern.
Home