Characterization of Pore Structure of Fuel Cell Components ：的燃料电池组件的孔结构表征.ppt

DR. AKSHAYA JENA AND DR. KRISHNA GUPTA
POROUS MATERIALS, INC.,
ITHACA, NEW YORK, USA
Characterization of Pore Structure of Fuel ponents for Enhancing Performance
Outline
Introduction
Through pore throat diameter, distribution, gas permeability & surface area by:
Capillary Flow Porometry
Capillary Condensation Flow Porometry
Hydrophobic through and blind pore volume & distribution by:
Vacuapore
Through pore volume, diameter, distribution & liquid permeability by:
Liquid Extrusion Porosimetry
Summary and Conclusion
Introduction
Pore structure governs ics of physicochemical processes & Flows of reactants and products in fuel cells.
Quantitative measurement of pore structure is essential for Design, development and performance evaluation.
Technologies for pore structure measurement are currently being developed to characterize plex pore structure of fuel ponents.
We will discuss several innovative techniques essfully developed and applied for evaluation of pore structure of fuel ponents.
Through Pore Throat Diameters, Distribution, Gas Permeability and Surface Area
Importance of Such Properties
Through Pores:
Fluid flow
Pore Diameters:
Capillary forces for liquid movement
Throat diameters:
Separation of undesirable particles
Gas permeability:
Overall rate of the processes
Through pore surface area:
Physicochemical processes
Effects of stress, chemical environments & temperature:
Influence of operating conditions
Suitable Characterization Techniques
Advanced Capillary Flow Porometry
Capillary Condensation Flow Porometry
Through Pore Throat Diameters, Distribution, Gas Permeability and Surface Area
Advanced Capillary Flow Porometry
For wetting liquid:
Wetting Liquids fill pores spontaneously
e out spontaneously
A pressurized inert gas can displace liquid from pores provided:
Work done by Gas = Increase in Interfacial Free Energy
Basic Principle
Advanced Capillary Flow Porometry
Pressure needed to displace liquid from a pore:
p = 4 γ cos θ/ D