Single Side Catalyst (Pt/C or IrO2) Coated Membrane (CCM) for PEM Water Electrolyzer, CPEMWESSCCM

In Proton Exchange Membrane Water Electrolysis (PEMWE), a Catalyst Coated Membrane (CCM) is the primary configuration for high-performance systems. In this setup, the electrocatalysts are deposited directly onto the polymer electrolyte membrane, creating a seamless interface that minimizes ionic resistance.

The two primary methods for integrating catalysts into an electrolyzer are CCM and CCS. (1) CCM (Catalyst Coated Membrane): The catalyst "ink" is applied directly to the membrane. This is the industry standard for PEMWE because it provides superior interfacial contact, leading to better catalyst utilization and lower electrical losses. (2) CCS (Catalyst Coated Substrate): The catalyst is coated onto the Porous Transport Layer (PTL)—usually a titanium felt or carbon paper—which is then pressed against the membrane. While easier to manufacture because it avoids membrane swelling during coating, it typically has higher contact resistance.

Ultrasonic spray coating is a common lab-scale and pilot-scale method to make high quality CCM. The high-frequency vibrations atomize the catalyst ink into a fine mist, producing highly porous and uniform layers while preventing the membrane from "puckering" or swelling excessively.