Scientists have demonstrated a proof-of-concept three dimensional paper-based microbial fuel cell (or MFC) that could take advantage of capillary action in order to guide the liquids through the MFC system and completely get rid of the need for external power.

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Scientists have demonstrated a proof-of-concept three dimensional paper-based microbial fuel cell (or MFC) that could take advantage of capillary action in order to guide the liquids through the MFC system and completely get rid of the need for external power.