https://www.nature.com/articles/s41467-022-32652-y https://www.nature.com/articles/s41467-022-32652-y Presuming I understood correctly. Another system used a

https://www.nature.com/articles/s41467-022-32652-y https://www.nature.com/articles/s41467-022-32652-y Presuming I understood correctly. Another system used a hydrogen-side electrode made of foamed metal immersed in water, where the surface area presented to the water was therefore very large, and the small pore size limited the hydrogen bubbles' interference with contact between water and electrode surface.