Applications and Characteristics of Porous Titanium in Hydrogen Fuel Cells
I. Applications of Porous Titanium in Hydrogen Fuel Cells
- Gas Diffusion Layer (GDL)
- Function: A core component for gas (hydrogen/oxygen) transport and water management in fuel cells.
- Advantages:
- High Porosity and Connectivity: Ensures uniform gas distribution to the catalyst layer, preventing local concentration polarization.
- Corrosion Resistance: Superior long-term stability in acidic/alkaline electrolytes (e.g., proton exchange membrane fuel cells) compared to traditional carbon-based materials.
- Mechanical Strength: Supports membrane electrode assemblies (MEAs) to prevent structural collapse.
- Bipolar Plate
- Function: Separates individual cells, conducts current, and distributes reactant gases.
- Advantages:
- Lightweight: Density is one-third that of graphite bipolar plates, significantly reducing fuel cell stack weight (critical for automotive applications).
- High Conductivity: Surface conductivity exceeds 1000 S/cm, minimizing ohmic losses.
- Corrosion Resistance: The TiO₂ passive layer resists acidic corrosion, extending service life.
- Catalyst Support
- Function: Loads noble metal catalysts (e.g., platinum, Pt) to enhance electrochemical activity.
- Advantages:
- High Surface Area: Porous structures increase active site exposure, improving catalyst utilization.
- Stability: Titanium’s chemical inertness prevents carrier corrosion and catalyst detachment (unlike carbon supports, which degrade via oxidation).
- Conductivity: Acts as a conductive backbone, reducing interfacial resistance.
- Flow Field Plate
- Function: Guides reactant gas flow and removes generated water.
- Advantages:
- Customizable Channel Designs: Complex flow channels (e.g., serpentine, interdigitated) via 3D printing optimize gas distribution and water removal.
- High-Pressure Resistance: Strong porous titanium suits high-pressure fuel cell systems.