A novel hierarchically-porous diamondized polyacrylonitrile sponge-like electrodes for acetaminophen electrochemical detection

A novel composite electrode material consisting of tangled fibrous polyacrylonitrile-based hierarchically-structured nanocomposites has been produced by wet-spinning, carbonized and decorated with a carbon nanoarchitecture by microwave plasma-enhanced chemical vapor deposition and investigated as a metal-free electrode for the enhanced electrochemical detection of acetaminophen. Surprisingly, the hierarchical fiber architecture is the result of the synergistic action between surface etching, by the H2 plasma, and nanostructure formation, by the C- and CH- radicals, which significantly affect the porosity and electrochemical performance. Moreover, by simultaneously conducting fiber carbonization and surface functionalization, it is possible to dramatically reduce the manufacturing time and to confer an 18-fold increase of the acetaminophen detection sensitivity, due to the sp2-C defect-rich overgrown nanostructure, which represents a preferable site for the drug adsorption, as supported by the molecular dynamics simulation results. Because of the excellent performance, and the simple and scalable production method, the prepared composite is a promising candidate as a metal-free electrochemical sensor.