Why PEM Electrolyzers Prefer Platinum-Plated Titanium Mesh and Titanium Felt

PEM electrolyzers, as an important energy conversion technology, demand extremely stringent material requirements in practical applications. In this context, the choice of appropriate materials, especially for the anode-side flow field plates or diffuser materials, is particularly critical. This article will delve into why Platinum-Plated Titanium Mesh and Platinum Coated Titanium Felt are chosen for these applications instead of directly using titanium materials.

Platinum-Plated Titanium Mesh and Titanium Felt

Platinum-plated titanium mesh is made from expanded titanium that has been flattened and annealed to ensure the surface is smooth and even. The platinum-plated titanium mesh can replace the carbon-based gas diffusion layer (GDL) used in fuel cells. Similarly, platinum-coated titanium felt is made from compressed and annealed titanium fibers that are sintered to form a flat surface. Through our unique platinum-plating process, we significantly increase the material's service life.

Platinum-Plated Titanium Mesh

Platinum-Plated Titanium Felt

Why use platinum-plated titanium mesh/felt?

Untreated titanium mesh/felt will not be consumed as carbon-based gas diffusion layers are, but the presence of oxygen does have an impact if the electrolyzer operates at a pressure slightly above atmospheric pressure (1-3 bar). Uncoated titanium felt rapidly forms an electrically insulating oxide layer (TiO₂) under high oxygen pressures, increasing the interfacial resistance in the cell and thus reducing electrochemical performance, affecting reaction efficiency.

What can a platinum coating achieve?

The primary function of the platinum coating is to maintain the conductivity of the titanium mesh to meet the demands of stringent applications. This ensures a longer service life for the battery or for pressurized electrolyzer applications (up to 450 psi). In industry, it has been observed that platinum-plated titanium mesh/felt can be used on the anode side of PEM electrolyzers under such pressure values. The platinum metal loading on the platinum-plated titanium mesh can reach 60–80 micrograms per square centimeter of the base material's physical dimensions.

Reasons for no longer using carbon-based gas diffusion layers

Because the electrolysis reaction rapidly oxidizes carbon to CO₂ (in acidic media) or CO₃^2- (in alkaline media), carbon-based gas diffusion layers (GDL) cannot be used on the oxygen-evolving electrode of the electrolyzer hardware. This phenomenon leads to poor stack compression and increased resistance, hence, selecting platinum-plated titanium mesh and titanium felt becomes a more viable alternative

In conclusion, platinum-plated titanium mesh/felt offers advantages in PEM electrolyzers for maintaining conductivity, extending service life, and adapting to high-pressure environments, making it an ideal material for flow field plates and diffusers. We offer customized membrane electrode assemblies (MEA) and catalyst-coated membranes (CCM) to meet various needs. This also includes MEA testing for microbial or PEM fuel cells, MEAs for chemical processes, and other specialized applications. Through these optimized materials and custom services, we provide more reliable and efficient solutions to our customers.