Designing a cathode for electrolysis

This morning I was watching a video about they’re using 3D printing to increase the surface area of a scaffold for growing cells inside a bioreactor:

It made me think about how we may like to increase the size of the biofilm when growing hydrogen-oxidizing bacteria, and how metal 3D printing has gotten a lot cheaper and more accessible over the years.

Why don’t we design a cathode with a large surface area? Using JLC’s 3D printing service we can print in stainless steel, which is exactly what we want, right? That should allow us to grow more bacteria, or at least more biofilm, in a small space.

Large surface area is good, but it needs to be a large surface area that we can easily harvest HOB from. No biofilm or a self detaching biofilm would likely be easiest.