Pyrolyzed chitin nanofiber paper as a three-dimensional porous and defective nanocarbon for photosensing and energy storage

The design of the three-dimensional (3D) porous and defective molecular structure of nanocarbons can potentially enhance their functionalities for advanced electronic applications by providing a large working volume, rapid transport of electrolytes and reactants, and active sites for electrochemical reactions. Here, we report successful fabrication of 3D porous and defective nanocarbons by direct pyrolysis of crab shell-derived chitin nanofiber paper. The pyrolyzed chitin nanofiber paper has tunable electrical resistivity (1013 to 10−2 Ω cm), 3D porous structures with layered nanofiber networks, and defective nitrogen-doped carbon molecular structures. The pyrolyzed chitin nanofiber paper shows good performance as a photosensor and an energy-storage supercapacitor electrode, proving that the tailored 3D porous and defective carbon structures play key roles in the drastic improvement of the performance. This pioneering approach can be used for fabrication of chitin nanofiber-derived nanocarbons with excellent multiple functions for future sustainable electronics.