Power-on-paper: Origami-inspired fabrication of 3-D microbial fuel cells

We demonstrate that fabricating low-cost microbial fuel cells (MFCs) can be done efficiently by using a paper substrate and origami techniques. A 3-D MFC was developed from a 2-D sheet of paper by integrating the anode, reservoir, cation exchange membrane (CEM) and air-cathode. The cell was easily formed by folding the paper along pre-defined creases. The entirely paper-based all-printed MFC developed in this work rapidly generated power with a small amount of bacteria-containing liquid through rapid adsorption and instant attachment of the bacteria cells to the anode. A graphite-polymer composite and graphite ink with activated carbon were readily applicable as novel anodic materials on paper and enhanced performance better than a conventional graphite ink or gold anode. The hydrophobic wax-based CEM was readily built with a commercially available wax printer and using heat to control how deep the wax penetrated the paper. This work will create a novel platform for paper-based power source, stepping toward batch-fabricable flexible papertronics.