Hello,

I am currently conducting research on Microbial Fuel Cells (MFCs) and have completed several batches of experiments. I believe there should be some improvement to my experiment, as the biofilm did not form as I expected.

My MFC utilizes a 3 mm-thick graphite sheet as the anode, connected by a stainless-steel wire to the cathode. The connection was made by drilling a hole in the graphite sheet so it could be hung onto the wire. Some parts of the wire were submerged in the anolyte, which contained bacteria and growth media.

Biofilms were always visible on the stainless-steel wire but not on the bioanode. Other observations when disassembling the system included finding holes in the submerged part of the wire (possibly due to metal-reducing bacteria in the anolyte) and noticing multi-colored marks (when directed towards light) around the wiring area on the bioanode.

What might be causing the biofilms to grow on the wire instead of the anode? Is there anything I can do to promote biofilm growth on the bioanode?

Also, if I raise the wire so it is not submerged in the anolyte (to prevent the wire from being reduced), will this affect the electron transfer between the anode and the wire?

Thank you in advance. I greatly appreciate every response to my questions.

*Attached within this post are pictures of the biofilm and bioanode.