Highly conductive and stretchable conductors fabricated from bacterial cellulose

Advanced materials that can remain electrically conductive under substantial elastic stretch and bending have attracted extensive interest recently owing to their broad application potentials, particularly for flexible electronics. Here, we have developed a simple and inexpensive method to fabricate highly conductive and stretchable composites using bacterial cellulose (BC) pellicles as starting materials, which can be produced in large amounts on an industrial scale via a microbial fermentation process. The prepared pyrolyzed BC (p-BC)/polydimethylsiloxane (PDMS) composites exhibit a high electrical conductivity of 0.20-0.41 S cm(-1), which is much higher than conventional carbon nanotubes and graphene-based composites. More importantly, the p-BC/PDMS composites that combine high stretchability with high conductivity show great electromechanical stability. Even after 1000 stretching cycles at the maximum strain of 80%, the resistance of the composites increased by only similar to 10%. The resistance increased slightly (similar to 4%) after 5000 bending cycles with a maximum bending radius of 1.0 mm. NPG Asia Materials (2012) 4, e19; doi: 10.1038/am.2012.34; published online 1 June 2012