Functionalization of Stress-Activated Pyrolytic Carbons (SAPCs) for Biofuel Cell Application
Carbon is one of the most adaptable element due to its unique flexibility in atomic composition to form sp, sp3, and sp3 hybridize covalent bonds with various elements [4,19,18]. Depending on its atomic conformation, carbon can greatly vary, ranging from a fully sp3-bonded crystalline network like a diamond to a fully-sp3 bonded 2-D structure like graphite. Each of the allotropes also have vastly different electrical, mechanical, thermal and chemical properties which have led to its adoption in the realms of biotechnology, electronics and energy storage [5,34,30]. Particularly, in the fields of materials sciences, carbon nanomaterials have become an excellent model system to study the impact of nanoscale defects on electrochemistry that can potentially be use as biosensors or wastewater filtration. However, fabrication of such materials is still arduous due to its tendency to break easily or inflexibility to mold. C-MEMS fabrication technology is, therefore, to address these challenges to engineer 3-D structures of carbon. However, chemically-inert surface of these carbons still makes its implementation for various electrochemical application problematic. Although various methods have been introduced to functionalize carbons, these processes can be unstable, detrimental to microfeatures of carbon and time-consuming due to additional step of activation. Herein, we show a new class of carbon, stress-activated pyrolytic carbons (SAPCs), that has a highly-graphitic structure with abundance in edge planes and nitrogen heteroatoms without external activation steps. In this study, we reveal an outstanding capacity of SAPCs as a promising material for improving laccase-driven electrocatalysis in biofuel cell application.