High-throughput fabrication of carbonized electrospun polyacrylonitrile/poly(acrylic acid) nanofibers with additives for enhanced electrochemical sensing

Abstract

Lightweight, polyacrylonitrile-derived electrodes with different additives were fabricated using high-throughput nozzle-free electrospinning. The electrospun precursor nanofibers (PNFs) containing iron oxide, gold nanoparticles, or reduced graphene oxide (rGO) were subjected to oxidative stabilization and carbonization to obtain a carbon-rich conductive nanofiber structure. Scanning electron microscopy showed that the carbon nanofibers contracted between 11 and 55% while the Fourier-transform infrared spectroscopy confirmed that the carbon nanofibers were thermally stable. Thermogravimetric and differential scanning calorimetry results revealed that the cross-linking of the chain molecules and cyclization were completed. Next, cyclic voltammetry results indicated that the electroactivity of the modified screen-printed carbon electrodes was decreased by 85% due to the presence of carbon glue. The modified device presented significant enhanced electrochemical responses with the inclusions of nanoparticles, with rGO showing a 2.13 times higher electroactive surface area, followed by iron oxide (two times) and gold nanoparticles (1.37 times) than the equivalent PNFs.