To tackle anthropogenic climate change, the large-scale production and use of green hydrogen stand out as a key solution for replacing technologies dependent on fossil fuels. Achieving this, however, necessitates substantial amounts of electricity from renewable energy sources and the rapid expansion of electrolyser capacities. Notably, the production of green hydrogen using polymer electrolyte membrane (PEM) electrolysers relies heavily on the catalytic materials iridium and platinum. Due to the Earth's limited supply of these metals and their extensive use in other industries, scaling up electrolysis operations faces significant resource constraints. Addressing these challenges is essential for enabling a sustainable and cost-effective growth of green hydrogen production.