The PEM electrolysis hydrogen production technology utilizes a proton exchange membrane (PEM) as a key component and has numerous advantages and challenges. Here is an analysis of the technology:
- Electrocatalysts: In PEM electrolysis cells, the anode operates in a strong acidic environment, requiring electrocatalysts with acid resistance and high potential corrosion resistance. Commonly used anode electrocatalysts include noble metals such as iridium and platinum group catalysts, as well as their alloys and mixed oxides. Researchers are also exploring non-noble metal or non-metal catalysts, but their practical applications are mainly focused on iridium-based catalysts due to the requirements of the reaction conditions.
- Membrane Materials: Commonly used membrane materials in PEM electrolysis cells include DuPont’s Nafion series membranes, Dow’s series membranes, Asahi Glass Co.’s Flemion series membranes, Asahi Kasei Corporation’s Aciplex-S series membranes, and Tokuyama Corporation’s Neosepta-F, among others. Among them, DSMTM membranes have good mechanical properties, thin thickness, and good dimensional stability, making them perform better in practical applications.
- Membrane Electrodes: The anode of PEM electrolysis requires acid resistance, high potential corrosion resistance, and an appropriate porous structure for gas and water permeation. Currently, researchers have developed various membrane electrode materials, such as 3M’s nanoscale thin film (NSTF) electrodes and Proton’s directly sprayed deposition method for membrane electrodes. These membrane electrode materials use noble metal catalysts (such as iridium and platinum) to enhance the performance of the electrolysis cell.
- Bipolar Plates: Bipolar plates and flow fields account for a significant cost proportion in PEM electrolysis cells. To prevent corrosion of bipolar plates, protective measures such as applying a corrosion-resistant coating on the surface are commonly employed. For example, titanium and platinum layers can be prepared on stainless steel bipolar plates to improve corrosion resistance and conductivity. Researchers also use additive manufacturing techniques to fabricate stainless steel material flow fields with directly deposited mesh gas diffusion layers to enhance the performance of the electrolysis cell.
In summary, PEM electrolysis hydrogen production technology offers several advantages, such as high hydrogen gas purity, rapid response capability, low ohmic resistance, and compact size. However, challenges still exist, including the high cost and stability of electrocatalysts, performance and durability of the membrane, and the cost of bipolar plates. Future research and development efforts will continue to focus on improving these key technologies to further advance and apply PEM electrolysis hydrogen production technology.